I had two days on these bindings. The first day out of the box was great, incredible feel and control. The toe strap is designed to work in both over the toe and toecap mode, for my boots (Salomon Malamute) the toecap option would not hold well and kept slowly sliding back in to over the toe positionnot a big deal and probably boot dependent.
Now the bad news; on the second day of riding while unstrapping, I noticed that the heelcup on the right binding had broken. It appears that the Zytel material fractured at a stress point where the heelcup meets the bolt that adjoins it to the baseplate. I would have assumed it was a one time random flaw in the injection mold of that individual part if I didn't see that another backcountry customer review had the exact same experience with this binding.
I think Union is a good company and maybe there was a bad batch in the molding process. I am going to give the MC MetaFuse another shot and will report back here on any issues.
Again, when they were performing properly they were an amazing piece of gear, but given my experience I cannot recommend them at this time.