Well, Ive watched 4 full length Iso's without issue. I used the full blu-ray menu on all, and other than some slow load times (just like Blu players a few years ago), I don't have any complaints. Really like it so far. I noticed on my SD card, that I used to expand the unit memory from 16mb to 2gb's, several gigs are added after watching a movie. I'm not sure if this is the running of the Java or what, but it's real easy to clear after you are done.