So I'm thinking of getting the iphone 3G and using it on T-mobile with YESSIM (ATT sucks and I'm not paying $140 per month for the same plan and only $90 a month but with better service from T-mobile) and I'm wondering if anyone is using YESSIM with T-mobile (or any provider other than ATT). What's the longest any of you have been using it and how is it working out for you? Sorry if all this has been covered before (I searched and didnt come up wth too much info) I just dont want to waste my money on something that isnt gonna work.