CDMA vs GSM TP2: What is really different between the two?

[sshanky]

I have tried to find the answer to this but haven't been able to.

I have a Sprint TP2 (unlocked of course), and am thinking of moving to T-Mobile. I suspect I would have to do a radio upgrade, although this is still new to me. The real question is this: Will I be able to use the fast 3G data T-Mobile provides if I do this? Or will I be restricted to EDGE speeds?

I know there is a different section on this forum for GSM and CDMA versions of the phone, but still can't figure out exactly why -- are the phones totally different in terms of hardware, or can the Sprint (CDMA) version be made to function just like a GSM version with proper hacking?

Thanks a lot!