I just got my Teensy 2.0 ++ in the mail this morning. Got it flashed, got the backup manager installed, and started ripping Armored Core 4 to the internal drive to see if I notice any difference in loading speed and the like.
The backup process is slow, and the percentage complete indicator isn't very accurate at all -- it has been on 83% for at least 15 minutes now, but it continues to copy different files so it doesn't seem to be stuck. Hopefully speed (or at least accuracy of feedback) will be improved in the future.
It would also be great if someone could figure out how to have an estimate of the harddrive space that will be used by a given game available before you start ripping, so you don't try to rip a game that's going to take 16GB on to a drive with only 8GB remaining and have to start all over, say.