Originally Posted by Spreggy
Maybe I'm one of the few who noticed that the OP didn't want to spend the $120 on Ortlieb if he can help it. I've used a $25 grocery bag pannier for 3 years, still going strong. The plastic bag I put my laptop in when it rains didn't cost me a penny.
For a college student carting laptop and books and bulky things, a pair of grocery bag panniers would rock the party, imho. A pair of rain covers and he's ready for anything.
________________________________________________________________________
I am only an occasional commuter and would not recommend the performance bike grocery pannier without mods. It tends to 'bounce' around over the rough stuff and isn't securely fastened at the bottom (bottom of bag bounces against rack that is). I suppose this is the trade off for a lower priced 'quick release' open top type of bag. This is probably fine for clothes in another bag/lunch, etc, but I would be hesitant to leave anything fragile or of value (e.g. laptop) in it while riding. Of course, your mileage may vary.
Since they aren't cheap, I would recommend some other means if that is the primary concern.. If you have a rack how about a milk crate bolted down. You can then put any other bag, etc. in it and feel confident it isn't going anywhere if secured at the top. Even if purchased new, you could probably purchase both with hardware for ~25 bucks.