That metal one is for 1" threaded, and I wouldn't want metal that thin anywhere near my carbon steerer. I've pored over Peter White's site, as well as BUMM.DE looking at the various brackets. The B&M 471B/1 looks possible, but it doesn't appear to have a way to lock in place on the steerer tube. It's keyed for a threaded tube.
I received the Axiom clamp, and I think it's going to work. It had a lip on the edge to keep it from falling down the seat tube, but that ground off easily enough with my Dremel, The black paint on it was helpful to spot if any part of the lip was left - I'd hate for that to be a point of stress when clamped.