I'm currently thinking of switching to Sprint for $79.99 unlimited everything plan. But as of right now I can't decide what device I'd buy. The Nexus S 4G is Pure Google and will get all Google updates first-hand, but on the other hand I wouldn't feel comfortable sticking with a single-core phone for 2 years. The Evo 3D has the 1.2GHz dual core processor and Sense 3.0 (which I love) but I'm worried about the battery life. Which would you choose?