I dropped a cut down T-Mobile PAYG sim in my iPhone 4 after a friend was talking about how much faster his speeds became contract became after he switched from PAYG. Do they limit the speed of the PAYT Sim's i get like 190kbps and 55kbps (which is much slower than he got) See the pic below..

http://yfrog.com/mrphotokp

From what i have read T-mobile only give standard 3g on pay and go and pay monthly plans. To get HSDPA you need to be on pay monthly and pay for their web addon.

I get 450kbs max on my sim only with internet booster no HSDPA.

http://support.t-mobile.co.uk/discus...43e3f34700681c

Yeah, this is broadly what I've read too i.e. HSDPA on T-Mobile is tariff dependant.

Oddly enough, the easiest way to get HSDPA via the T-Mobile network is to go on Virgin Mobile where, if you have HSDPA coverage, you will receive HSDPA speeds whether you're on PAYG or contract.