Agreed. Unlimited data is the only reason I stay with Sprint. I have a choice of two carriers where I live and AT&T is 3x faster, but Sprint is unlimited. I don't care about speed if I can't use my phone past the 3rd week of the month.
And even if Sprint offered "unlimited" 4G in my area I wouldn't go with the because I know "unlimited" is complete bullshit. I'd rather a company be honest form the start. Not tell me unlimited but really it's 2 GB then throttled to dail-up speed afterwards.
The only sense in which Sprint does "throttle" per say is based on on current tower useage like any other carrier. Once a tower gets "full" they allow everyone to get an equal slice of the pie. But this metric doesn't take into past data usage.
This is very different from the straight 128kbps cap ATT throws on their "unlimited" users that use too much data.