Iphone 4s with T Mobile Data Plan Question

I will eventually get the simple choice plan or the walmart 30 dollar plan, not sure if i qualify for this or not because i will be buying a used iphone 4s unlocked.
I know the simple choice plan 50+ is unlimited minutes, data and text but data is 4g up to 2.5gb then its 2g since most phones are 4g capable.
I know the iphone 4s is not 4g capable… so that means with this plan, it will be 3g up to 2.5gb for the month and then 2g? Or would it be 2g the entire way? I can not imagine it be 2g the entire way but this plan doesn’t seem to say 3g anymore?

Moderator Warning

This is an official warning.

Pauly01, you have been starting too many threads about mobile phones and mobile service, and were given clear instructions to restrict all further posts on this topic to your already existing threads. Today you started two new threads in clear violation of these instructions. You are therefore issued a warning for failure to follow moderator instructions.

Thread closed.