It seems people on the CDRW boards are saying that the 32X Lite-On is a bit more picky about media. ie. the 32X doesn't write as well at 32X to crappy media as does the 24X does at 24X, for obvious reasons.
Also, sometimes when my friend burns at full speed to cheap media, they work fine in his own machine and in my Mac's Toshiba drive, but my PC drives cannot read them consistently.
For important stuff I burn 24X on Mitsui 24X media ($$$). For throwaways to be read by my own drive only, I burn on whatever cheap media I happen to have at the time.