Those Carradice bags are AWESOME. I've never seen those before. So Freddly!
However, my concern is they are true saddle bags, as in they are attached to the bike with buckels. I would need this for commuting with my work clothes, which I would bring in to the office (17th floor) to change into. During the day the bag would hold my helmet, shoes, and other riding gear.
I could still work, but it would need to be a bag in a bag, with my lunch in an other bag...