There is one big change I would make - I would put carrying handles on the top. I didn't have them, and without them it made carrying them up stairs and such a bit of a pain in the butt, and it also made it more difficult to attach them to the racks.
The attachment system did not work out well at all (let me be clear that it was the system I asked for, not one Chris came up with). The whatever-they're-called wouldn't stay closed. I used shoelaces tied to the top rack for a couple of days until we could get a better replacement. I used a different strap system that worked out fine for the rest of the trip, but came away from the trip thinking that clips really are an easy way to go for putting panniers on racks. My buddy bought two sets of Ortlieb clips and mailed them to me - I'm going to rig them to the panniers next time I use them.
Other than that, the panniers did great. Plenty of room, plenty durable (for road touring), I'll definitely use them next time I do a tour. Again, the only changes I'd make is to put handles on the top for carrying (I'll rig a sling for the one's I have) and I'm going to try the Ortlieb clips for attaching to racks.
Hope this is helpful.