Ken,
I asked the same question over a year ago on Trad Gang and got fewer responses than you have. I was looking for something lighter than a Screaming Eagle, but as sturdy and safe with the SE's high seat, no nylon strap for attachment, large platform, etc. I finally ordered a brochure. Looks like it uses steel cable for attachment to the tree (SE uses a heavy chain), but what concerned me was that the locking mechanism appears to be a lever clamp (for lack of a better description) located right behing your calf. Looked to me as if you could accidentally release the clamp if you weren't careful. Thus, I decided to stick with my Screaming Eagles.
Maybe Bowhawk can address the attachment system. I never heard from any one that had ever used one.