Hello to the forum. I have a 27/i5 3.2/1 To FD/10.8.4. Everything runs smooth. Still can't find out if it's worth going 10.8.5. Read all the posts I could but depicted problems seem to affect the OP or a few Mac users. I ask cause I think now is not the time to go upgrade to Mavericks. For me ML is good as it is. Really appreciate your input. Thanks a lot.