Regarding the Nashbar Action-Pack 'n Pannier, it is a total piece of crap. I got it on sale for $45, and I can honestly say it's the worst $45 I ever spent. Mounting system is inadequately weak, the pannier fell off all the time. The material tore after it fell off the bike a few times, nicer panniers would hold up better (or not fall off in the first place). When I replaced the mounting system with a a homemade upgrade, it worked fine for about a week, before the zipper that holds it on the bike broke, thus rending the whole thing useless. The backplate is weak, and flexy and generally inadequate. Also, the size is awkward, it's HUGE, too big for student use that it's marketed for, and if you fill it up all the way the pannier just isn't strong enough to hold all the weight.

All in all, avoid this product.

I'd really recommend the Arkel Bug. A very well designed pannier, I used it for four year before giving it to my wife who has been using it for the past year. The new version looks even better.