Needed more heel space. Was hitting panniers when I used them. This rack is positioned further back and gives plenty of room. Has lots of holes for adjusting to different tire sizes, only I didn't have to move anything, so I don't know anything about the adjustment. Sturdy, solid, seems perfect after 100 mile trip.
I have this on two different bikes, both with disk brakes, one as a front rack (fat bike with 26x4.0 tires), and the other as a rear. Mounting hardware is well thought, but doesn't include bolts if you'e using the plated steel bracket. A trip to the hardware store for some M6 bolts, washers, & nuts worked well. I've used these with panniers full of groceries, canned foods, 1 gallon jugs, and they hold up well.