@mylemsky chris_logan is right that I had an injury while using them, but I think I would have gotten injured in almost anything on the fall. I had a really large torque on my knee and just didnt release soon enough. Anyway, the other reason is that they are badly designed for the release method. On a set of Fogmans, the base plate is made of a rigid alum or G10 plate. The Quattro's have a flexible plastic plate. With a release pin configuration like this, the tighter you set the release, the harder it should be to release right? Well, that is so if you have a rigid plate. If you have a flexible plate, the greater tension you set on the pin makes the plate want to buckle off of the ski more and thus requires more interloc. It's just a huge mess to get the balance right so that it releases properly. If you don't machine your own plate for it, I would not go with that set up.