Just saying but if your total minutes of call is less than 100 minutes, then it wouldn't matter if you've called a number of DiGi operator, Maxis or U Mobile operator as it would be deducted from your free call given in the U58 or UMI48 anyway.

Some of the disadvantages of DiGi Smartplan 58
- Free calls and SMS to DiGi numbers only
- Quota are separated(so if you've managed to finish up your 1gb quota of surfing, then you'll be limited to a slow speed or need to use Opera Mini instead of being able to use the other 1gb quota)

Anyway, let's go to the main point:
Choose the following plan based on the following criteria/needs:

OverSeas Roaming
------------------------
U58
- better internet connectivity
- need to call people of different operators

DiGi Smartplan 58
- 95% and above of the time calling to DiGi numbers
- 95% and above of the time smsing to DiGi numbers
- slower internet speed

No Overseas Roaming(limited to Singapore only)
-----------------------------------------------------------
UMI48
- better internet connectivity
- need to call people of different operators

This is made based on the requirement whereby you'll need 2gb of data quota, and 100 minutes of free calls.

In terms of the charges at the end of each month, UMI48 would hold the least charges among the three, then U58 and Smartplan 58, that is if 95% of your contacts is not DiGi. If 95% of your contact are DiGi subscribers then it'll be UMI48, Smartplan 58(covered by free calls and sms) then only U58(U58 doesn't ship with free sms so it'll cost you another ~100 more fees of sms).

In the end, I'll suggest U58 if you need overseas roaming and UMI48 if you don't need overseas roaming 

NOTE: 95% is just an approximation, your mileage may vary.
No actual calculations are being done as I've made quite a few calculation mistakes in the past so I'll just explain it in terms of wordings 

Not that I know of. yes and yeap.

Based on my calculation, on top of the RM48, you'll need to pay another 30 more sms fees(since there's 30 free sms shipped by the UMI 48 plan, 60 - 30 = 30).
Considering the most experience condition as the base:
= 48 + 30 * 0.08(sms to other operators)
= 48 + 2.4
= RM 50.4

If you really do call 100 minutes per month, then you'll probably have to pay another RM 2 - 3 since the call blocks are charged at 1 minute(theoreotically you can call up to 100 minutes, but if you make 100 calls, the receipient accepted it and dropped the call for 100 times then it is considered as "100" minutes as well).

Setting that aside, I would suggest you to top up RM100 for the first time, then RM50 for the subsequent reloads. The remaining of amount of the RM100 reload will be used to handle the possible extra charges that is outside of the plan that needs to be paid. I would not suggest reloading RM50 every time as it would be like playing a deathmatch(what if you need to sms but no credit  ).

Repeat the step of reloading RM100 when your credit is low.

Yes. It is based on an auto-subscription method. They will sms you a few days before it is due and another sms if you've passed the date(I'm not sure whether they allowed you to have another day extra or not, it seems to say so in the text but I can't confirm bout it)

That is not exactly true actually. The "free calls and sms" that they've mentioned is the "free calls and sms" given when you reload, and not the "free calls and sms" given by the UMI plan. There's no time restriction for the "free calls and sms" given by the UMI plan.

This is the "free calls and sms"  that the support rep have told you about: http://www.u.com.my/prepaid/free_sms_and_calls

MNP. Find yourself a MNP guy at here or go to U Mobile's store 

It depends on your needs. If you need whatever that a postpaid plan provide(auto billing, statement, and overseas roaming), go for u58. If you don't need those, go for UMI48, its cheaper. Unlimited in terms of? If you look at the signal, then it is a hit and miss for both of them, some are good at here but bad at there while some are good at here and still, bad at there.

U Mobile does not support any LTE bands as of now and there's no date of it being rolled on so none of us here can say anything(unless there's an insider here  )

If you're talking about the free calls and sms given by the reload, then it depends on the number of days that you've reloaded(RM 50 = 50 days, I'm not particularly sure about the free sms but I think that you get to text 26 sms to u mobile numbers at the price of 6 sms)

If you're talking about the free calls and sms given by the plan, then refer to below

I'm not calling you to do that every month though    just for the first month only. and I think that the next time you reload another 100 is like another 1 - 2 years later    I've suggested as so so that you don't need to reload twice each month(50 + 10, or 30 + 30 like what you've said), just do the painstaking reload once and reload just once per month.

Assuming that you overbudget by RM4 per month(which makes it RM48 + 4 = RM52 per month), and the leftover of  the initial RM100 that you've reloaded(which is 100 - 48 = RM52), the RM52 can last you for 13 months(52/4)

My idea(reload RM100 first then reload RM50 for the subsequent reload) for a period of 14 months
Number of reloads = 14(1 RM100 + 13 RM 50)

Your idea(reload RM50 + RM10 or RM30 + RM30 per month)  for a period of 14 months
number of reloads = 28(14 RM50 + 14 RM 10 / 14 RM 30 + 14 RM 30)

My idea has higher initial cost but less hassle along the way.

Anyway, the maths between UMI48 and U58;
Assumption: 100 minutes of calls to all operators + 100 sms to all operators + 2gb data.

Data quota is out of the scope as both of it meets your requirements and both of it are 2gb, which is your requirement.

u58
----
Calls: RM 0 since 200 minutes of free calls to all operators are given, that is more than your initial requirement
SMS: This plan doesn't ship with free sms so you gotta pay extra for it.

Lower Limit - SMS only umobile numbers
--------------------------------------------------
= 100 sms * RM 0.05
= RM 5

Upper Limit - SMS to only other operators
---------------------------------------------------
= 100 sms * RM 0.12
= RM 12

So, your usage should be within RM 5 and RM 12.

Additional Charge(taking the upper limit as the base): RM12
Payment at the end of the month: RM 58 + RM 12 = RM 70

UMI48
--------
Calls: RM 0 since 100 minutes of free calls to all operators are given, which is equivalent to your initial requirement
SMS: This plan ships with 30 free sms to all operators, but unfortunately still not enough in your case so you need to pay another 70 more fees of sms

Lower Limit - SMS only umobile numbers
--------------------------------------------------
= 70 sms * RM 0.03
= RM 2.10

Upper Limit - SMS to only other operators
---------------------------------------------------
= 70 sms * RM 0.08
= RM 5.60

So, your usage should be within RM 2.10 and RM 5.60.

Additional Charge: RM 5.60
Payment at the end of the month: RM 48 + RM 5.60 = RM 53.60

End of Maths
----------------
u58(RM70) vs UMI48(RM 53.60)

which one do you want to choose? 

yup. In my experience, the speed has been pretty good, much better than DiGi's 3g in quite some places(I use DiGi as well)

I'm using UMI28 as I need internet connection for surfing + some free calls and sms. I'm a pretty light user so I don't think that it'll suit you much

err....... it is really location dependent. I have faced an issue of whereby there's signal indicated at the phone but I can't call or sms to others. Gotta reboot or set to airplane mode and turn it off then only can use. Others have reported such issues as well.

There's one member who reported that there's a total loss of connection at a certain place a kl, once pass there then ok 

I did had quite a good speed at jb when I went there last time, but it has been a while and the connection can drop or improve 

For my experience, U Mobile's network is pretty stable, but once it gets slow then it'll become something like DiGi's 3g(DiGi's edge is totally not usable for me  )  DiGi's 3g can get pretty good as well, but it is pretty limited in terms of location 

anyway, go and get yourself a prepaid and do a test drive yourself, if good then join the bandwagon 

yes, you will.

my answer is only for your 1st question actually    I'll confirm with you back regarding the promotion as it should have ended but somehow it is still shown at u mobile's site

so far the promotion still carry on... don worry.