I'm a long time fan of the commuter bag. It's Mary Poppins-ish in it's capacity, laptop just disappears, never filled it commuting, got a stupid amount of grocery shopping in it. Took it for a long weekend it France, room for 2 bottles of wine and the rest of the leftovers from the 100€ hamper we won on top of my clothes, shoes, camera, etc etc. It's neat, low center of gravity, doesn't interfere with pedalling etc etc.



However, I picked up a carradice bag for the Dunwich Dynamo, and hardly had my other bag out since. Keep it for when I tour, or need to lug a laptop around again.



The carradice SQR doesn't go near the seat post clamps. I've not had any problem with the seat post clamps, but I did, um, snap the rails on my OEM saddle a year ago. Blamed the bag I had hanging from it.

(the mezzo bag has to be removed before folding, the carradice can be left in place though it does move the center of gravity very high when folded, and if you don't rotate the saddle, makes a much larger package on public transport.)