I love OS X and everything is no fuss and predictable except for one thing -- external hard drives. I constantly have troubles getting consistent performance and I get really strange Finder issues. I have a 2010 Macbook Pro by the way. For example, I tried copying a 172 GB iPhoto library from one external drive to another external drive and one time it would finish in a few hours, and another time I did it, it said it would take over a day. I could see the progress go per megabyte. Another issue is that copying files to other hard drives will complete normally, but the file sizes will be off by megabytes. Another weird issue is that Finder/desktop will occasionally beach ball or not show files and folders; or I can't shut down/sleep/restart my computer. As soon as I pull out all the connected hard drives (I can't even eject it safely. The icons just grey out as if it were ejecting, but it never does), files will show in Finder or desktop and the shut down process immediately commences. I've repaired permissions, and tried old/clean installs, and gone through whatever operating system came with my 2010 Macbook Pro and every version since, and I'm even on Mavericks DP right now, but still have the same issue. I've gone from the stock hard drive to my Crucial M4 SSD and still get the same issue. I'm at my wits' end and would love to hear if anyone has any solutions?