I'm heading off to school next year and am getting a PowerBook to take. I have the option of either a 12in or 15in PowerBook, and, surprising though it may seem, I'm having a little trouble deciding. I like the bigger screen and power of the 15in, but the 12in is much easier to carry, and quite frankly I think the lid feels more solid (the 15in has a larger space between the lid and the keyboard). I'm not sure how much I"ll be carrying around the PowerBook. Do you guys think I should go with 15in or 12in?