I'm so incredibly happy with my 15" PowerBook G4 1GHz. I never had any problems with keyboard marks on the screen or uneven illumination or weird latches or anything, it's just worked perfectly from the get-go.
The screen is very impressive, although coming from a design background, and having been used to a 1600x1200 resolution on my 17" CRT monitor, the DPI of the screen seems extremely small for a while. Thus, I have it hooked up to my CRT all the time at home, which is a great setup at the moment. I also have an old original iMac keyboard plugged in at home, which is good, because the computer sits over at a weird angle otherwise. I also bought a two-button scroll-wheel optical mouse for use everywhere because I don't like using the Trackpad if I can help it.
I don't have the illumination controls on the screen or keyboard, but they're things I can live without (although I'm starting to wish I had them). I also don't have a SuperDrive, but that's OK at the moment - I'll upgrade later if I have to. I use the Bluetooth and AirPort Extreme cards all the time.
I DO wish it had IrDA though, for syncing to phones without Bluetooth...