I agree with most of the points made above. I rank visibility pretty important--yellow or light grey or lime green are great safety colors. Also, a problem with my Trek panniers is that they straps are easy to forget to fasten and they will rattle in my spokes. And the panniers are not comfortable to carry or keep set upright on the ground. Not even when the they are filled and bottom-heavy--panniers will fall sideways, which is SUPER COOL when you are transporting a dozen eggs. (I love being able to just fill rubbermaid containers and put them on my Xtracycle.)