My only comment about bones has nothing to do with knives. The carver himself mentioned the rotary knife blasting through bones. My point on bones in schwarma cones:The bones are a defect in the food product.
Either really. It doesn't take much more skill to sharpen a curved blade than a straight one, and not much more time to learn either, The scimitar would look really cool... especially if it is big! But I'd trade the toque for a fez or a taqiyah.
More professional... No doubt. The price seem to run $100 to $500. Didn't look at the difference between these offerings though. I suppose it depends on budget. The schwarma isn't likely to taste and better cut with expensive knives than it would cut with bargain knives. As long as the food/service quality is high and the knife is sharp enough to cut.