I think they are... With all those different laces and that wire, it really clamps your feet in... It was very comfortable to, only thing i didnt like (which could of just been that pair) was some part near the top of the binding was rubbing against my lower calf.. Not sure if it was the pair i was useing of if they all were like that
I dont think any of the Hyperlites are very stiff, I had an ankle injury last year, been riding 30/60's and Byerly's , this year switched to LF Exos. Lot stiffer overlay rubber, more ankle support, but harder to get in/out.
I have had bad ankles for many years, and it was really hindering my wakeboarding enjoyment. I went out and tried on every Hyperlite binding and the Highbacks were definitely the stiffest. I bought the 03's, then the 04's came out about a month later, and they are definitely a step above. When the 04's go on mega sale (probably end of next season), I will step up and buy some.
Check mine out, very supportive,if they are too supportive just loosen the laces. Plus you can do them for under $200. 02 ultras with 03 belmont overlays over the top of everything I have super bad ankles and these really help.