There's micros stutter only with 3D BD ISO's as they play at 24Hz. If you don't mind 3D you don't have to worry about it. All else playback fine with proper 23.976Hz.
Only in the case of interlaced videos, there's no proper auto freque switching. For 25fps interlaced you can set it manually to the proper 50Hz, and for 29.97fps interlaced manually set it to 60Hz (so not exactly 59.94Hz).
Also: all latest firmwares have a bug with .srt subtitles (lines are skipping sometimes). FW 2.0.6 doesn't have this issue, but it has a bug with a couple of hundred ms audio slipping, but just on the analogue outputs, so passthrough mode is not concerned.
That's all more important I guess, in a nutshell.