i know them from experience:
I used to have a blackberry they last longer it wasnt a touchscreen one but heres the breakdown:
Slide phone with qwerty keyboard:
they last longer
the screen and the whole phone is practically more duriable
touch screen:
they get shot after a year
you have to buy a...
it depends what u like? for the sony ericson is like the psp from sony. so if ur in to playing game get that but it is too big. so i would reccomend the samsung galaxy mini.
you would have to call them up but i believe my brother used to do that because he used to have the 50 dollar plan from tmobile and when he was at my hosue where he lives he didnt use the compnays data just the house wifi
i would reccomend going to verizon att or sprint since they offer iphones now. i would suggest that because they have better rates and plans and tmobile rips off everyone and if u explain ur situation to sprint or verizon they should hook up ur 3gs but im not sure for verizon because they use...