I have/had the trek interchange. I really like it. But, operator error (me) has caused me to have only one pannier left. My trunk rack bounced off one early morning because (I assume) I didn't click it in correctly. This was at 4:30am and by 5am, theives were already using my charge cards. Then, on my first commute this year, I again (I know this to be the case) didn't click my bag on correctly and was going down a hill, hit a pothole and the bag bounced off. I didn't know I lost it and a guy in a truck caught up to me and told me. It got lodged under another vehicle and all but destroyed.

That being said, I really liked these bags. I have/had them for 3 years and they were/are (the one pannier bag left) is very handy, has a built in rain cover and clicks on/off easy.

Operator error was my downfall, but I have to admit, they are nice.