JohnLaiThese are what I have studied/use more (ie Yoodo, Redone, Digi, Unifi, Yes). Celcom, Umobile, Tunetalk, XOX etc not right for me, so when I mentioned cheapest/more expensive, am only comparing Yoodo, Redone, Digi, Unifi

--For monthly, Yoodo is the best/cheapest

--There are plans such as XOX with long validity and supposedly good price (can't really understand the plan though) but beware that XOX sms can have problems. 1 forumer mentioned that XOX prides itself to be spam free until bank sms can be considered spam. Haha!

--Redone postpaid cheapest is $8/month + SST(usually about 50 cents) for 1 GB data. They don't have 2GB. The next cheapest is around $28+

--Unifi bebas is good if you can get it as there is no expiry date as long as you use a bit of it/top up a bit each time (limit to 1 sim card per customer). Not sure whether it still comes with free 10GB LTE data. The top up is a bit complicated due to division between 4g/3g etc, so you may want to see the website

Yes--am only family with konfem 4G which is $30/mth for unlimited data capped at 4MBps. They have other plans but I'm not familiar

In terms of price per call/sms, digi is the most expensive.
My Digi plan-- calls@26 cents and sms@20 cents
However, if you need to call/sms Singapore, Digi is the cheapest

Yoodo calls and sms are the cheapest, followed  closely by Unifi. Redone calls/sms are more expensive (if to 'non-Redone 'prepaid/postpaid' users--a bit complicated here but still cheaper than Digi.

Suggest your sister get Unifi bebas and another telco sim card. It  really depends on her data usage etc.  Your sister's credit is really a lot, so I guess use it only when there are really good offers. Otherwise use other telco lines.

There's always a grace period for the telcos. So you don't need to renew it every month if don't need the data.

Bear in mind, when I studied the telco packages, some I didn't go into much depth /didn't study as it didn't suit me at all, so what  I say may not be suitable for you.

For prepaid

Always get Unifi first/back up due to non-expiration date for data/calls/sms as long as you top up minimum or just make a phone call/sms, the grace period will start from your last call/sms/top-up.
It's weekly, daily and 2 hours LTE coverage is unlimited data but not sure whether there's any speed cap or can tether
For mobile data, I still think Yoodo's prepaid is one of the best as it doesn't have tethering restriction or speed cap  and minimum spending is $12/30 days for 2GB. Can't remember how many days is Yoodo's grace period (60 or 90 days??)--so don't have to subscribe every month.

Yes konfem 4G @$30/month  does not allow any tethering and speed capped at 4MBbps. They have other plans but I think cheapest also $30.

For daily/weekly usage I am not that familiar as I don't use much mobile data (most telcos such as Unifi, digi do offer them)

Sorry, I can't be of much help here.

Guys,

I went to Digi centre to request for a new nano sim replacement cuz my existing one is micro sim on Fri.

But till today, the new sim still no service. all call still land on the old sim.

Usually how long it takes for digi to change the line to new sim?

In my very simple explanation:
For Yoodo, it is suitable if you prefer to customise the plan according to own usage, and pay the amount of the customised usage.

Both XOX (especially XOX Black) and Unifi Mobile do have something in common, which is well known for having data, minutes and SMS that can never go expire. The biggest difference will be how they're being charged.

Unifi Mobile, let's say you pay RM15 for 2GB (4G only) + 2GB (4G+3G) plan, you got the freedom to use as long as you want, and it won't expire. No monthly commitment. If not enough, you can subscribe more add-ons and stack it up (except unlimited data plans). Their unlimited data plans cannot tether hotspot.
As long you make any calls, send SMS or surf Internet within 90 days window, your line will remain active. Or else, your account will be terminated on the 91th day. In simple words, just don't leave your number unused for more than 90 days, as if you keep the SIM card into your drawer and forget about it just because you got the freedom of not paying anything.

XOX, let's say XOX Black for instance, you pay the lowest RM10/month plan, and you get 1GB and 20 mins to all network every month automatically. If not enough, you can subscribe to Season Pass and stack/pile your data, minutes and SMS that will never expire, as long you pay your monthly bills. You don't use it at all also never mind. XOX can use hotspot.

Choosing which plan suits you is one thing. Don't forget about network coverage too. Unifi Mobile's coverage, 4G network is mainly run by TM themselves, and TM's 4G coverage are basically quite rubbish as the network is many blind spot coverage and slower speeds, even they are improving fast in expanding coverage, so you could say that it can be worst or same as U Mobile's network now. (Please note that this is my personal opinion, and may not be applicable and apply to everyone). But you could also say that Unifi Mobile is better than U Mobile in a particular area in terms of speeds, so it really depends on location also. Just because a telco's overall network is bad, does not mean the telco won't perform well in a particular area. Since they are considered as new comer in mobile telco network, you can't compare much la, unlike the big 3 telco.
The 3G network will be on domestic roaming by Celcom. Although TM did previously announce that they'll have domestic roaming with Celcom 4G network as well, but not sure how is it being implemented now.
So in conclusion, do have an expectation that Unifi Mobile's coverage may not as wide and as good as you would expect. You might experience slow speeds and it often stays in 3G network.

As for XOX, it is an MVNO and they use Celcom network. So in terms of coverage, it is the same as you're using a Celcom network.

For Digi, they are more towards balanced, but not too hardcore low usage ones. Their focus is more on users that has average to high data usage ones. Not those very low usage, passive users that don't use much. Price varies from low to high monthly fees ones.

For U Mobile, they are more towards quantity than quality. They focus on users that want to pay less, but get unlimited stuff without bother much on network performance. But their plan offerings do have speed caps to certain services that even their T&C may not stated it. Best example will be Video-Onz, where all video streaming usage will throttle to 1.5Mbps, which is enough for 480p streaming. If you are a user that don't mind "meh" or slow speeds but willing to pay affordable price (as low as RM30/month) to get unlimited this data and that data, then you can consider U Mobile.

For Maxis and Celcom, they are more on quality than quantity, as they focus are on network performance and coverage, hence target on users that willing to pay higher monthly fees to get more usage allocations. You pay for what you get lo...

For Yes 4G, their LTE speeds are pretty much average. As for coverage, city areas is fine, but when you go rural areas or underground places, you might only get "Yes 4G" or "Emergency calls only". There's no 2G or 3G because Yes 4G mobile service only operates in LTE. You must make sure your phone can support Yes 4G's LTE network, which runs on LTE Band 38 and 40 (2600MHz and 2300MHz TDD LTE), newer phone models shouldn't be a problem, as well as unofficially Band 20 (800MHz). And also VoLTE too, or else you can't make and receive phone calls. Yes 4G's VoLTE are not supported on all iPhone models, only Android can, at least for now. Meaning if you insist using Yes 4G on an iPhone, you can only use mobile data but can't make/receive phone calls.

thanks.

Contacted Digi on live chat, they said no record of sim replacement request on system.
Lousy Digi service by Nu Sentral branch ...

JohnLai Thanks for that. But in Malaysia Boleh Land where everything also boleh, ummmm....don't expect too much if you know what I mean.
alexanderclz If I do shoot on Digi to MCMC, I need to shoot Yoodo first. They have not bothered to refund me even after several complaints. Guess they just don't want to refund.

[4lt4ir] Subscribed for Roam Like Home but while still in Malaysia, already no network. Sim card went completely dead on me  but after several days, became ok again. Have already read up on whatever it is needed to activate the RLH but never got a chance to do it.

Don't dare to complain to MCMC because now I'm using their booster plan for my data instead of paying the normal data plan. If they really look into my plan as they said they will but still currently never bothered to get back to me, scared wait they know how users are smartly utilizing their booster plan and stop the booster offer.  So may just have to accept my loss.

err what do you mean I am shouted about? I am sharing the experience as for today as it will be very seldom for digi will accept the blacklisted name due to bad trade reference across the telcos.

yes yes.. every infos are appreciated.. even when someone came here and rant about their prob.. no need to eat heart (makan hati) k.. 
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like me.. i went to digi store express in the weekend to replace my sim.. don't u guys think that newer sims are too manja? only scratched a lil bit, cannot read liao.. my sim only 1 year and 7 months old.. so frustrated u know..
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old days sim seems to be more durable.. like my celllcom xplore sim over 10 years still work..
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so.. been charged for rm10 for their cap ayam sim smart chip.. maybe next year i'll have to replace again.. 
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that's my story.. rant a lil bit.. hehehe...