A friend of mine has the bug and loves it. I've ridden with her biking to a hike, and the conversion was very quick. My approach has been to use a small day pack (http://www.rei.com/product/778466 which inverts so there are no loose straps and attach it to the top of my rack. The load is balanced rather than one-sided like a single pannier, but of course it takes some time to convert from bike pack to day pack this way.