ok i have a few...issues....with my g5 1.8ghz.
a lot of times, i cant get the damned thing to sleep! whether it be in the finder or from the power button.
another problem is that it will not play the startup chime over my speakers, it always plays it over the internal speaker. though not a big deal, its annoying.
final issue, and its a biggie. it takes more than 5 tries (regularly) for it to recognize my Unreal Tournament 2004 DVD. other DVDroms anmd movies have no issues whatsoever