I've got three Macs detailed as follows:

one Intel iMac 2GHz with 2GB RAM
one PowerMac Dual 867Mhz G4 with 2 GB RAM
one PowerBook G4 1.5GHz with 1.25GB RAM

I use Maya on both the PowerMac and the iMac.
I also use Lightwave 9, Photoshop CS3, Shake and Final Cut Express.

Personally I prefer the PowerMac over the Intel iMac but hey each to their own.

I've mostly been getting crashes when running Photoshop, usually when crunching HDR images, but that was on the Intel powered iMac.
Incidently the PowerBook G4 12" actually handles them better (hasn't crashed) but with less RAM is not the best machine to use.
So far the dual G4 PowerMac is handling the files very while it's a smidging slower than the Intel iMac but I can live with that.

I am going to upgrade the CPU's with the Sonnet Encore Duet MDX G4 1.8GHz CPU module when I have enough pennies sorted.

Cheers

Chris