I picked up one of the Tru-Turn prop hubs, intending to use it on an Astro Hog with OS-70 four stroke. It's pretty long on the front of the plane; 1/2" longer than the Higley jam nut / acorn nut combo. I can't decide if I like it for the Hog.

I've been looking at the Sportsman Waco 60 biplane as a possible future plane. With the big round cowl, the Tru-Turn setup might look better on it.