If you can get past the ridiculous price tag, the Ortlieb Vario does exactly what it advertises -- a single pannier that can hook on to a rack or be used as a backpack. The conversion is simple and all the moving parts are reinforced to reduce wear and tear. I commute 2x a week and walk 2x a week, so this has eliminated the need to transfer all of my work stuff from pannier to backpack. The laptop sleeve is and outside pocket are much appreciated details. I'm not surprised they're sold out. Highly recommend.