I am looking into buying a used Mac off of ebay as a second system. I am looking at a G4 450 with 512mb ram... is that going to be too slow for the applications I want to run such as design software (Photoshop, Flash) and some video editing (Final Cut, Premiere, After Effects)? It doesnt have to run these programs blazing fast but it has to be usable. If its too slow what speed should I look at? Thanks for any advice.