I got my hand's on a set of the Vipec's during the '14/'15 season in New Zealand. Previously I had been touring on a Marker Duke, so no matter which tech direction I went, the drop in weight was a game changer.
I have the first gen. mounted on my Rocky Mountain Underground Apostles. So accustomed to the feel of a down hill binding, I was extremely hesitant about how these new things would ski. They're awesome; I have been floored on numerous occasions as to just how well they handle steep, hard pack conditions and a ton of torsional stress. The pin system is great and the binding handles, downhill, just as well as my Dukes'.
On the ascent, the binding preforms phenomenally in almost all aspects. The binding is super light and all the actions are smooth. I was the ski tech at Small Planet Sports, New Zealand's largest backcountry outfitter, so I spent a lot of time mounting and fixing almost every tech binding available. One of the large advantages I noticed in the shop, before ever skiing them myself, is that the Vipec's heel piece moves in a strictly front to back motion, which alleviates a lot of stress that the Dynafit binding's endure with their clockwise transition's in the heel. By not following the Dyanfit program, the Vipec is able to use a lot more plastic, to save weight, without having to worry about wear and tear from movements unrelated to the actual skiing of the binding. Time and time again, I had Dynafit binding's come in for repair due to the snapping of the rubber pad that helps protect the heel piece as it spins clockwise. I love the risers and transitioning from walk to ski, without leaving the binding is almost effortless.
The Vipec does have a major downside, an issue they have made progress on correcting with the second generation; I can't step into the toe piece without using my pole to open the wings. I'm pretty sure the problem stems from their introduction of the din releasable toe piece. It is a great idea and the binding has only ever released on me in situations where I would also expect my Look Pivot's to let go, but the din spring, when cranked above two, put enough pressure on the system that the wings begin to close in on each other, thus not leaving enough room for the boot to fluidly step in.
I have about 30 days in on these bindings and have put them through some unnecessary beatings, to test their strength; the wear and tear has been minimal and they are yet to break or fail me. All that said, I would highly recommend these bindings, but my feeling is that the tech systems are going through such a revolutionary phase that no one company has the perfect system. The newly redesigned Dynafit Beast toe piece has caught my eye and I look forward to getting a new pair of these Vipec's in the future.