not really but I know what you're talking about. Most of the tie down webbing that connects to fasteks are polypropelene or dacron and it does deteriorate eventually. The problem with Fastek buckles is that they really aren't mean to carry lots of force or cyclical forces. They work best as quick release and quick connect with working loads a lot less than the working load of the webbing. So a boat cover with 1/2" fastek gets connected and pulled TIGHT and then the weight of the wind hits repeatedly it or the next time the buckle is clipped and a 200lb person pulls HARD it breaks. For use connecting to racks or belts I don't see a problem but for applications where a load cycles or is very high it doesn't last. Like the 1" webbing and buckles used to suspend a 65lb kayak with static load it's no problem but if the load varies from 20-65lbs it can lead to failure. On kayaks they're used a lot to clip across hard shell hatch covers but if a person grabs the kayak by the strap it can snap.

I'd use fastek buckles to hold things on bicycle racks but if the bags were hanging down where weight was cycling on the straps I'd want some kind of backup if the buckles were narrow 1/2" size. Somehow I broke one of the tangs on the fastek buckle that straps over the top of my Ortlieb roller pannier. I jammed it in wrong and it broke. Surprised me.