I've got a pair of them mounted to a T7. They're a very stiff binding, and also quite light. The highback is carbon fiber reinforced with a plastic/frp frame behind it.
The ratchets are butter smooth, the toe strap is nice, although lately I've noticed it slipping on my boot just a bit. Highback forward lean angle is easily adjustable. Overall I've been trilled with them, wish I had bought non-ESTs so I could mount them to a Kessler or Oxess board cause I think these are as good or better than the race bindings (just my subjective thoughts)...