I've been using Axiom Appalachian bags now for nearly two years. They were dirt cheap (under $30). I NEVER expected them to hold up so well with daily year round commuting. The bags are always stuffed. Once side is filled with foul weather gear and extra cloths. The other side is filled with all the food and drink I need to get through a days. The only down side is that these are saddle bags so they are not the easiest to remove and hook-up. Otherwise these are a descent side, in expensive, remarkably water proof and durable. The Ortleib bags look like they are much nicer, but you'll spend 6 times as much on a set of their bags.

Happy riding,
André