been exact same position, when i got the contract i asked if the 3g was capped they said no, before i was on a tmobile 500mb and unlimited browsing and speeds was 20+ mb , so i upgraded to full monty and right away my speeds went to 4mb , called them a few times and was told no caps and depends on area, ya right, then finally i got to someone who said yes speeds are capped, and will increase it to 10mb i said fine, noting happened called again and was told same, and to this day no increase, so i just gave up
i have 6 months left on my contract , as soon it ends im going to Three with there free 4g unlimited package, also had some Freud on my t mobile contract, which someone upgraded without me requesting it , and they even received a phone,
so i cant wait to leave, my mates are on three and there speeds are very good using in same locations as me