I was extremely hesitant to make the transition to low tech bindings because I like to ski fast, aggressively on wider skis and jump as well as a lot of negative publicity about earlier editions of dynafits and other low tech bindings having release, mechanical and reliability issues.
I use these with Scarpa Freedom SL boots on Kastle TX 107 skis. I weigh 160 pounds. I tested these in the Northeast in and out of resort on ice, groomers, moguls, spring touring on Mount Washington, sleet, powder and all the funky conditions we get in the northeast for ten days in spring 2014.
These bindings perform incredibly well on touring mode. I went from using alpine trekkers to these so the contrast was astounding. I also briefly used Marker tours prior to using these. The lightweight as well as the low profile of these make them very performant touring and climbing steep hardpack slopes in frozen spring snow conditions. Be sure to engage the lock position when touring up steeper slopes at an angle as they have both released at the same time on two occurences (not fun especially when carrying heavy pack).
This is where I was most impressed. This binding skis like a high performance alpine binding (Tyrolia freeflex, Look px). I put the DIN at 9 (same DIN on alpine bindings) and did not experience any release issues. The power transfer is like an alpine binding. I did not notice any difficulty in steering the wide powder ski (107 mm at skate). Even skiing the zipperline in the mogul course, I forgot I was on a touring binding. Even though I set my bindings at DIN 9, I believe it was the right decision to get this model that goes up to 12 instead of the other one that only goes to 10.
The lever to engage the binding in lock position is located at the front of the binding. It is possible that it may inadvertently become engaged while the user is skiing without user's knowledge, thus leading to a potential serious knee injury.