I've toured in all kinds of weather, and it will rain... Sometimes a little, sometimes a lot. No bag will keep your gear completly dry, if on tour and its raining when you need to set up camp water will get in your bags, or in the morning when you pack up, the morning dew will get in your bags... or stuff that nasty T-shirt you have been waring for three days into your bag..

I was on tour along the Gulf coast of Fla. using a set of roll top bags, The first three days went well, on the forth day I had to set up camp in a light ran, that night it really started raining but by morning the rain had stopped, the skies had cleared and the sun was shining... Perfect day for riding. That night when I stopped to set up camp I opened the bag... and WHEW! it must have been a perfect enviroment for the molds to form. (Warm,dark and humid) Everything stank and was moldy... That was the last time I used those bags, or that tent, sleep pad, shorts etc.... But my touring is a little more back woods then a lot of people car for.