I had a PowerBook G4 and the a MacBook Pro but I'm back on generic laptops now - I got increasingly annoyed with paying over the odds for hardware only for it to be used to almost force me to pay for software - you can't use this OS because your laptop is too old, so you can't use this version on iTunes, so you can't use your phone and so on.
I now have a fairly low spec laptop running Lubuntu (lightweight Ubuntu) and it's totally fine. I can boot to Windows if I want, but generally I don't; I only use it for Garmin update software for my satnav.
When I went back to Windows (obviously the laptop came with it, so I gave it a go) it was a bit of a shock, hence moving to Linux. And then when, two years later, I needed to use Windows again, the updates took two days.