It's all about what you like. I'd go AMD XP over a P4. I have an AMD XP 2100+ (1.73) and every review I see it's compared with a 2.2 P4, and it out performes it and only costs about $70 at
GoogleGear. So you could take the $150 or so that you would spend on a 2.4 P4 and get a AMD XP chip. The 2400+ is only $80 right now. I'd take that over the P4 any day of the week.