I had already a good experience with the standard ASS-Savers. But for riding my bike AFTER heavy rainshowers I bought three of the extended version. Well, nothing can protect you completely from the mud raised by spinning cycle wheels. But nothing protected me better on my race bike than the extended ASS-Savers. Just very few tiny little spots on my back. And this for just a few grams more... Two of my cycling buddies will be happy in the near future, too. Thanks, ASS-Savers.