I've tried everything, but for me a
good backpack is more comfortable and rides better than a messenger bag, though it doesn't quite have the messenger bag's easy access. Like ghettocruiser mentioned, I like to be able to hop curbs and such, and even a lightly loaded pannier impairs my mobility more than I'd like. Also, I sometimes venture offroad on the way home (Portland's Forest Park isn't very far out of the way), and when the going gets rough I find it works better to carry my load on my back than on a rack. Plus ... I don't want to have to have a rack on my bike.
Originally Posted by cerewa
For me, there are two significant problems with carrying stuff on my back:
my backpack doesn't protect the stuff in it from rain, and it makes my back get sweaty and stinky. (so then my backpack gets sweaty and stinky too.)
Get a Vaude pack and you'll solve both problems! They have a built-in Safety Yellow raincover that stows in a hidden pocket when not in use, and keeps everything dry (even my laptop) when in use. Their Aeroflex-equipped models have a stay in the back that provides an airspace between the pack and most of your back, wiping out (so to speak) the sweat factor.
I've been commuting with their Siena 40 (and, in nice weather when I have less stuff to carry, the Dash 10) for almost 5 years now, and it's been bulletproof.
Here are the mtbr reviews for the Siena series -- scroll down to the one by "Dan W" and you'll see
my review, from 4 years ago. Still going strong, although they don't make the Sienas anymore. Here's their current bike-pack lineup. Look for the Air models with the "Aeroflex" back:
http://www.vaude.de/hps/client/vaude...hbs/outdoor/en