Originally Posted by CrazyMike
+1 for the Jesse pizza box.
I also have the 35L pizza box with 10" Odyssey panniers. For my tastes, it's either one or the pair. I've had my cases since this past January and I've only ridden with all three maybe once. The topcase is used for general commuting and day rides, while I use the panniers for longer, generally overnight, trips.
Na. I use the topcase only for commute and daily stuff - a pizza box would do me no good there, as neither my (unfortunately big) laptop bagpack, nor two helmets, nor one helmet and a jacket would fit in there.
On longer trips I use an Ortlieb bag for tent, cooking stuff and sleeping pads. This wouldn't fit in the pizza box either.