With zero commission war between brokers for US market I think Charles schwab is the winner.
The question is whether you can open it as a Malaysian or not.

If you cannot have access to those zero commision brokers, then yes interactive broker is the cheapest.
If you op for pure interactive broker and if you choose tiered pricing (the cheapest option)  is few cents per transaction. If few cents I won't even bother counting.

If you have no money for pure interactive broker like yours truly and op for whitelabels (rebranded version of interactive broker by other companies but still interactive broker), it cost about USD2-4 depending on which whitelabels are you using.

If you opened your acc with the link via TSG website, then it's already linked.

HAA!! You have the same problem as me! Now you need to restart!!

When you start instarem from the very beginning, even before verification, you chose a country already. And once chosen, it cannot be changed! You can only transfer money from your country of residence (or chosen country).

If you choose SG in the beginning, you can only send SGD.

I'm confused... you're trying to send MYR using InstaRem to your CIMB (SG) acc right?

then you need to create a new acc (with a different email address) with Malaysia as your country of residence (from the very beginning). Then you can send MYR via InstaRem.

I see. You are talking about this part.
If you can choose to send MYR, then you've selected Malaysia. You're on the right track.
No need to re-start.

Just choose any country. I know it sounds stupid... but it works.

Normally how long would it take to get TSG account approved ya?
My application and my funding was done around 28 Nov, until now it's pending status...

Just dropped an email to them..Hopefully no problem 

https://www.interactivebrokers.com/en/home.php

from here

Wanted to ask, why don’t just transfer USD from a local bank USD account to Interactive Broker?

I just opened a multi currency account at HSBC. How do you guys transfer the USD money to the IBKR account?

Personally tested and it worked!
Transferwise EUR
InstaRem EUR, SGD, HKD.

Personally tested but it failed!
Transferwise USD
InstaRem USD

meaning, IBKR can accept SGD, HKD, EUR, just not USD, from InstraRem, Transferwise.

you actually don't need a S'porean bank acc.

Hmm,

I have been a IB user for years... Using their TWS to trade. Trust me IB has one of the most advance platforms out there, but not very user friendly. Eg the idealpro vs fxconc, till now I still don't know which one I used and how I did the  forex change.

Glad to find this thread going and I will be trying to contribute as much as possible.

I see most of the questions already answered by friendly bros in this thread. Only one point I want to make. Touchwood. This applies to all foreign companies platform actually. One bad thing about trading using online non-malaysia company platform is that (again touchwood) if something happens to you, it will be very difficult to claim the money.

Even if you manage to claim the money, do note you will be subjected to US Inheritance tax (they call it Estate Tax) even if you are a Malaysian (I checked this few years ago, not sure if still valid). Which is why even though you are a Malaysian and do not need to pay US tax, your stocks dividend will still be subjected 30% withholding tax.

Now I do not know if local stock brokers have this Inheritance tax or not since I do not have any now. So it would be good to check. For me I think I am going to start slowly moving the money back to Malaysia or Singapore. My friend who is a US citizen and has US bank account, he doesn't keep the money in online brokerage. He always transfer the money back.... because it is more secure. Anyway I am going off topic.

So for those who opens IB or any other online overseas platform, do take note:

1. In the event something happens to you and how to claim the money back
2. When you transfer the money back after making profits, if amount is big you might have issue with Bank Negara. Of course if less than 6 figures I doubt they care.

Cheers.

banks' exchange rate are not competitive(Wire/TT), they take about 3-5% of your money instantly while fintech companies take about 0.3-0.5%.

It is up to you to decide.