If you have an iBook, you won't be able to get a comparable G5. Apple never made a portable G5 in its iBook or PowerBook lines. You can get a G4, with some good deals on factory refurbs on Apple.com, or go Intel. If you have any Classic (Sys. 9) apps that you're not ready to toss, replace or upgrade (if they have OS X versions), the Intel route is problematic, involving unsupported emulation software and a performance hit. Absent any of those, Intel would be the way to go.