iMac G5 CD-R compatibility

Is it just me, or does the Superdrive (Matshita UJ-845) compatibility suck?

I can't get it to read:
Princo or Maxell CD-Rs that work fine in my PC's LG drive.

I called Apple support and they claimed it wouldn't work with the Princo's because they are rated to 56x. That's garbage! I was not impressed by how clueless they were.

The drive will read pressed CDs, and seems ok with some Kodak CD-Rs I have.

Is anyone else having trouble like this, or do I have a faulty drive?

Mine reads Princo's no problem. Perhaps it is something specific to the discs in question?
Thanks for your reply.

What does "About this Mac / More Info / Disc Burning" say your drive is? Mine says "MATSHITA DVD-R UJ-845" with Firmware DBN9. I understand there's a different model in some iMacs.

Any suggestions on how to talk to Apple support to get a useful answer or talk to someone who knows what they are talking about? The person I talked to was so clueless, they said (and this is a quote) "oh, those discs are too fast for your mac, it only has a 24x drive" when I said the Princo CD-Rs I was attempting to use were rated for 2x to 56x burn speeds.
Looks like this drive is really picky on the media types u put in. I tried to use verbatim dvd-rw and it spitted 'em right away (same dirve \ firmware as above).
Guess i'll have to look for another brand.
Any suggestions ???