I'm considering upgrading the stock 5400 RPM Hitachi drive in my macbook pro to the Seagate momentus XT (7200 RPM) hybrid drive. I'm curious about the experiences of those who may have done a similar upgrade: 1. Is there a noticeable difference in performance? I seem to do a lot of waiting for the HDD in my day to day usage and I suspect the increased spindle speed will be helpful. 2. Any noticeable tradeoff on battery life (>~10% or so)? 3. Should I expect an increase in heat or vibration? Finally, for those using the momentus XT I've been reading about issues with the dreaded beachball waiting for the drive to spin up. This lag would obviously defeat the purpose of upgrading and I'd like to hear about any personal experiences in this regard with the drive. Thanks in advance for any comments.