Hmm.. My experience seems substantially different from much of what's been said already, so ymmv, but I was at one point addicted to alprazolam (low dose, 1mg/day minimum 2mg max, but if I missed a day it would be guaranteed insomnia and very likely panic attack), and I began taking quetiapine (seroquel), and after a month or so I was able to taper my dose and eventually stop taking alprazolam all together. My anxiety was drastically lower, though part of that can be explained simply by quitting the benzo. Additionally, I found quetiapine to be an extraordinarily effective antidepressant. After the first three days of taking it, at some point in the morning I suddenly realized that I felt good in a way that I hadn't felt for a couple years. That was many years ago, and I continue to take quetiapine, and whenever I feel a depressive episode coming on I double my dose and stop it in its tracks, and then go back to my lower dose for sleep.
Note -- it can be really difficult to stop taking quetiapine after you've been taking it for a long time at doses around 200 mg or more. Lower doses don't seem to have this problem. This isn't the same as how it is difficult to stop taking benzos, however-- its more of a discontinuation syndrome than a withdrawal -- but either way it is something to take note of b/c no warning of this kind is included in the labeling and my doctor seemed skeptical when I told him my experience.
Anyway, like I said, ymmv, but my experience has been generally very positive, especially for the kind of situation you describe. It is not very useful recreationally and may mix poorly with downers until you become somewhat tolerant to the sedating effects. I'm glad it is no longer on patent b/c I'd feel reticent about writing such a glowing report about a monopoly protected substance, but now I can say guilt free that on balance it has been an extremely positive addition to my life.