I just tried QS0A, but I like QS09 better.
It limited my CMC 40x and 48x discs to 40x (they burned fine at 52x before).
The recording quality with TDK (Ritek) 40x discs at 52x wasn't as good as the same media and speed combination had been with QS09. In addition, SMART-BURN slowed the speed at the very end of the burn with the TDK discs, which it hadn't done with QS09.
Because of these changes, I reverted back to QS09.
Edit: I just noticed; congrats on 100 post, Tidus!