I have the 17" MacBook Pro.

1) It runs hot, although not nearly as hot as some of them I've read about. Keeping it on my lap can become uncomfortable if I don't rest only the edges on my legs. This would be more difficult to manage with the 15".

2) There's an odd, infrequent problem with the sound glitching that I haven't researched yet.

Battery life is about 2.5 to 3 hours, I'd guess, but I haven't really pushed it yet.

All in all it's a great machine, but I personally wouldn't put anything under 1G of RAM in it. I don't have any experience with the MacBooks so I can't give you a differential, other than to say that the Pro has a gorgeous keyboard. If the MacBook doesn't have the same, then the Pro might be worth it for the keyboard alone.