[quote name='The Mana Knight']PS1 compatibility is mostly universal, since they use the same emulator. I don't have the game on PS1 to test. I do know FFV has issues when saving.
Like I said before, the bluetooth has delay issues on any PS3 model, when playing PS1 games.[/quote]
It's not bluetooth. I've used a wired controller.
Unlike other games, Bust a Groove has a practice mode which definitively shows what's going on with the timing. The audio is simply not correlated with the video, and that will be the case no matter what controller is used.
I've read that Parappa 1 and Um Jammer Lammy have similar issues, but I haven't tried them recently.