I have unlimited data on Tmobile for 20 bucks...i think it's usually 30, but i've been with them for more than 7 years, so they gave me a deal when I thought about leaving a couple months ago. As long as I stay on it, I should be grandfathered on that price forever...so they tell me.
I like the EVO as well, bus as far as hardware goes, hang tight, there will be quite a few more phones in that same class coming out soon enough...everyone will have one under a different name. Another reason to wait...have you actually looked at the Sprint map of 4g coverage? I can't believe that they launched a 4g phone yet, let alone have the stones to charge you $10 extra to use it....it's like, tiny little pockets around a very small amount of major cities...pathetic. Everywhere else you be getting 3g performance for 4g prices.