Right now I have a G3 iBook (900 MHz, 640 MB RAM, Combodrive, 40 GB HDD). I'm looking at a G4 iBook (1.2 GHz, 768 MB RAM, Superdrive, 60 GB HDD). How much faster would the G4 be over my G3. I figure that after selling my G3, the G4 would only be another $200ish on top of it. Would this be worth it?