I've actually made two with horn handles so far. Hickory backed Jatoba and maple backed Jatoba. The hickory backed Jatoba is for an SCA shooter that is an actual serious archer as well and pulls 65 at 28. The maple backed one (pic) is for someone who wanted a "pretty bow" and was the first one I made (30 at 28). Near as I can tell the horn adds nothing to the draw or speed (at least the way I'm doing it) but does seem to reduce hand shock (maybe by stiffening the handle?).
Yes they pay me, but you gotta remember the bows I sell to them are PRETTY but not necessarily good shooters. When ine if them wants a good shooter its the rare one that appreciates the difficulty of making them. I paint Celtic knots on them, use exotic hardwoods in the risers (most of what I sell are flat bows with cut shelves) and crest the arrows in attractive patterns. I do spine match the arrow sets I sell, which has gotten me a reputation for selling good arrows (many of them have never experienced shooting a set that is consistent). Doing shooting demos and competing in their archery events helps. My overhead costs are low as I get most of my wood from a local trim shop that sells me the raw milled wood and let's me have scraps for free (risers and nock tips) of exotics.