Thanks anyone for the input!

Does anyone have actual cubic inches measurement (or liters if you are metrically inclined)?

That Toucan bag is pretty cool and looks really functional. What F8th867 said about buying too many bags scares me! I have a tendency to herd bags for myself (backpacks and work packs) and now I might get a bike-pannier addiction!!

I'm also going to Paris in July and am dedicating one whole afternoon at going to bike shops known for their bike bags inventory!!

Thanks for your help!