I also find PT under OSX is more sluggish compare to our set up under OS9, BUT, i beleive this issue is more due to the OSX as all our other apps including our Media100 video suite suite under OSX is also more sluggish. All our video and audio workstation are running with dual Processor Mac 1Ghz and up with more than 1Gb of ram in them so i don't think it's a problem with not having a fast enough CPU. OSX seems promising but it still has quite a ways to go.