Originally Posted by fuzz2050

I'm slightly baffled by this; my Ortleibs with the QL1 system go on in literal seconds. Less time than it takes to put on a backpack for sure. To be fair, they do weigh more than they have to, and are a pain to carry off the bike.

Messengers don't use them because messengers are style conscious (at least the ones you see on the media), dirt poor (being a messenger pays poorly) and often have to leave their bikes in theft prone places where a pannier might be stolen in the second it takes to remove.

I do some messenger-ish work (bike delivery) and my coworkers who use backpacks only do so because they can't bear the notion of spoiling their bike with a rack and panniers, or can't afford to spoil their bike with a rack and panniers.