2 Questions about HP DV6000t about processor and battery and about money

My first question is about the batery life with the different processors.
What battery life difference would i get with equal usage from
A: Intel(R) Core(TM) 2 Duo processor T5500 (1.66 GHz)
B: Intel(R) Core(TM) 2 Duo processor T7200 (2.0 GHz)

My second question is kinda a summish one. I have been reading about many people ordering their notebook and then canceling it. When they called to cancel they were offered 70-100 off the price or a refund in order not to cancel it. If i ordered option B and then called them Back and told them i wanted option A. What time frame would i have to do this in. The build date is December 13th for the 2.0 GHz option and November 30th for the 1.66GHz option. If i ordered the 2.0GHz and called next week to cancel would they still offer me a discount? or would i have to call like the week it would be built?

Thanks
Joseph

 

1.) VERY similar (read equal) battery life between the two processors.

I'm not sure about your second question, but it's not really ethical. You should order what you want. =/