If you've seen any of my other posts, I've been somewhat disappointed with ML because of the following: I can't sync Notes from Mail to my iPhone without iCloud or another network. i.e. no more direct transfers Too many bugs. Numerous applications (iWeb, iPhoto to name a few) don't work properly Poor performance compared to Snow Leopard or Lion Unbelievably long times taken to index the system via Spotlight, and full indexing re-occurs all too frequently Other odd performance bugs like the memory pegging for no apparent reason Problems with third party drivers bring the unit to a crawl I was hoping at least some of these would be fixed in 10.8.3, but I can't find any evidence they fixed any of them. I didn't expect them to fix the first item but I work in a secure environment and transferring data to iCloud or via another imap simply isn't allowed (we used to distribute work loads via Notes...our bosses solution is to look outside the Apple realm for replacement phones, probably Androids to replace all our iPhones...Apple's clearly outthought themselves on this one) In any case, for me at least, enough was enough. I've converted back to Lion. I gave serious thought to converting back to Snow Leopard, but it just seems a little dated now (don't flame me, I have another system with SL on it and I still think that was their best OS). Everything seems much faster now, and all my applications work, and the system finished indexing the drive of the same size as my ML volume in about 1/3rd the time (30 min vs. 90 min) and now I have TONS of free memory. I had a base Lion installation saved on a FireWire drive. Here's what I did for those interested: Cloned the Mountain Lion volume to another FireWire drive Cloned the base Lion install to the drive that used to hold Mountain Lion. Booted the system up under Lion with the now external FireWire drive containing Mountain Lion up. Used the rsync command to copy the contents of my user directory that was no Mountain Lion to the Lion volume. Caveats to be aware of: rsync is a command line tool and I'm not going to do a tutorial on it. I restored all the directories that I needed but not the Library directory, just the stuff I was sure would transfer properly. You can clone the drive several different ways. One way is to use a third party tool. Another, which is good if you have an old system with an active FireWire port around is to use the asr command. In Tiger this can clone a drive from drive A to drive B, even if drive B is smaller than A as long as there's free space available. A third way is to use the drive cloning procedure described in the following link: http://www.scsc-online.com/How-To.html I've been responding to another poster on this site because he was having drive problems, and we use SCSC's tool Scannerz. If it hadn't been for that I probably wouldn't have known they updated their site with that info. Anyway, the above technique will clone both the ML volume AND the recovery volume to the target drive, as long as the target drive is as big or bigger than the source drive. If you wish to clone to a smaller drive and you can find a Tiger system it can be done that way. Apple, I suspect modified asr because it was probably to easy to bootleg the OS using that tactic. The biggest problem you'll encounter transferring stuff is being careful with what you transfer from users Library directory. I was careful, but I also like to think I know what I'm doing. Reverse migrating Mail from ML to something like Snow Leopard may require an export from ML and then a full import to SL, which is a PIA. Now that I'm on Lion again, the system is quick and fast. I know some people have had problems with Lion, but I didn't after I got used to it. All my apps are working and I can sync notes to my iPhone without iCloud. If Apple ever gets ML working properly, I might migrate back to it again, after all it's sitting there on a Firewire drive. I remember that when Leopard first came out it wasn't all that impressive either, but they got the performance up over time. Hopefully they'll do the same with Mountain Lion, but until then...adios.