I was at 1.2 but the battery became more of an issue than my concern over the processor burning out. I refuse to spend extra cash on an extended battery. 1Ghz works well and seems to have decent battery life with uberkernel. I cannot say I saw a significantly imporved performance from my phone on 1.2 vs. 1.0 Ghz. I reccomend sticking whith the publically avaliable uberkernel. However, I will say overheating was never an issue for me so if you have an extended battery 1.2 may just be the kernel for you.
