Pretty cool, if the quality is good.
For those that can't afford to get an eMac or just want the challenge of super-boosting their existing machine, this is really nice.

The trouble with CPU upgrades is you've still got slow, out-of-date subsystems. By the time you upgrade the ones that matter you've spent almost as much or more than you would on a new system.

Plus, in my case, I think my Grape iMac's display is going south, and the slot drive has trouble kicking discs back out. I have an old monitor laying around, so a Mac Mini is tempting, but I hate to buy a new machine that's barely more powerful than my two year old iMac G4!

I have been wondering for a while if I could do the upgrade myself, using the G4 500 processor that I pulled out of my tower when I upgraded it's CPU. I have been holding on to it in case something happened with the replacement, but I have had no problems (kudos to OWC 1.33 gHz Mercury Extreme) and I would rather try the upgrade than face what either an old iMac DV or a used G4 CPU is worth on eBay. I bet there are a lot of other people out there who have pulled the slower processors out of old "Sawtooths" and still have them lying around. This could be a great way to upgrade an otherwise functional, but annoyingly slow G3 machine.
Besides that I would like to know if anyone has seen a way to "unlock" the mirror image display limiter on these machines the way that has been done on the eMac? (see below)

"Even though Apple limits its use only to mirroring the main screen, it is possible to lift that limit and run dual-screen configuration using AppleScript firmware updater from Klaus Rutemller."

http://www.rutemoeller.com/mp/ibook/ibook_e.html

I have four other mac's between home and work, but t would be really fun to trick this one out since it is an oldie AND a goodie. (gumdrop)

BTW aside from reluctant ejection of CD/DVDs this machine has always preformed great.