Do I need to wipe data/cache for this?
Yes
Also, I'm confused about the benchmarks people are saying they're getting.
That's 14mflops with 1.3Ghz on non-Froyo JIT. This is getting 12.5mflops on stock or 800mhz? What would you get with Froyo at 1.3ghz?
800mhz here
12.39mflops
running 2.2