Just this morning put a clean install of ML onto my brand new 830 SSD in my MBP. The 1st thing I have noticed that really wound me up in lion, was not being able to go back and forward through pages with the track pad in the app store!! As I was installing Black magic I noticed this was not the case in ML and happily went back and forward with the track pad. I got 390 write and 475 read by the way. Happy so far with that.