I think it really depends on where you want to go. For example, I've flown to ORD, ATL and RNO from DFW lately and I've been able to do much better with AA.com as long as I book 2 weeks (or more) in advance. On the other hand, if you are getting down to the last few days (I think Student Universe requires at least 4 days in advance, although I could be mistaken), SU is probably going to provide you with a good discount.

SU probably also will help you out in the event you are travelling on a route with little competition.

Follow up to an earlier post: this A.M. I logged on to AA.com and found that 2 out of 3 Qantas flights I took (with Student Universe tickets) were credited. The third was a flight from BNE to MEL which for some reason still has not shown up. At least the long legs have been awarded credit.

-z