Yea... probably 5~6 yrs ago... Had SE X1i back then. Was getting only EDGE speed...
Well, up till today, I am still using internet2.voicestream.com. Still pay $9.99 per month. Gets EDGE, 3G, and HSPA depending on area's coverage... (Must say that T-mobile's 3G/H coverage isn't as good as AT&T, but it's cheap...)
I use SE X10i, unlocked, running custom CM7 ROM. Had it for 2 yrs and never had problem with internet2.voicestream.com setting.
Therefore, chances of the same setting working is likely... @ least I'm betting ~$800 on it... =S