Pilot "Sport" Classic Binding?

I need bindings for new roller skis and am totally confused at what Salomon now offers for classic. The least expensive option is actually a "Sport" pilot binding that looks a lot like the skate binding (rigid piece that connects to second bar).

People have described a kevlar strap as part of the race classic pilot binding, but this version looks like it doesn't have that (so might actually be an improvement for roller-skiing). I have one pair pilot, one pair old-style profil classic boots--ideally I'd like to be able to use either, depending on how much ankle support I find I need.

Then there's the Propulse, which people say can only be used with newer pilot soled boots--though it's not clear why. Then there's old-style pilot (which, unfortunately, is actually out of stock from my discount source).

Any advice appreciated.

Jon