I’ve been looking at that bag too. I have panniers (KotoMoto). The zippers are starting to fray, after almost 4 years. I like that you can drop the panniers down and fold them up as needed. Might be my next bag.
The one requirement I have is for the bag to have clips, instead of zippers. Zippers can be hard to pull when you are wearing gloves. I guess I can put a paper clip in the hole of the zipper, but clips seem more manageable. Zippers exposed to the elements don’t last long. We get dense fog, that sometimes doesn’t burn off, and direct sun on other days. Couple those days with constant wind and they get beat pretty bad.
Maybe I’m scarred from school, but jam enough things in the bag and you’ll have a hell of a time zipping them up.