Asus 40x cdrw plextors and audio


I am finally replacing my old scsi plex and decided on the asus 40x. I did a search for asus and tried to read all the results. I guess what I need to know is;

Is the asus 40x better than the 48x in regards to media compatiblity and seek times, beating protections?
Is $83 too much for this drive? Is there any reason not to get it? Should I get the 48x for $93?
Should I keep the plex for audio protection?
Is the ultra plex wide going to be fast enough to write on the fly at 40x?
I am unsure of how audio protection works and I thought if I had a reader that could beat the protection, such as the Ultra plex wide, I could rip the audio using the Plex Wide and burn it with any burner. Is this correct?