I'm a composer, and up until now I've been running my whole setup off one (admittedly powerful) PC: Gigastudio, Cakewalk Sonar 3, and the Tascam FW-1884 Firewire audio board. All these things are great products, I think, but all together, I think they just asked too much of my PC, and it's been incredibly unstable of late, with the audio board crashing all the time and requiring restarts. So, I need another computer, and I've decided to take the plunge and enter the Mac world. As long as I'm getting a second computer, I wanted to take advantage of the portability of a Powerbook - I regularly travel from LA to San Francisco and New York, and it would be great to basically have a portable studio. Given that, though, is the 17" too big for this to be really practical? Assuming I get the same RAM in either (is 1 GB enough?), would I really miss that extra .08Ghz if I got the 15" 1.25Ghz model? Also, does anybody out there have experience doing sequencing work on one or both of the 15 and 17? - is the extra screen space really helpful/necessary, or is the 15 enough? (If anyone's got a recommendation between Digital Performer and Logic, I'd love to hear that too.) Thanks very much.