Willy is very laid back and sweet. I think the borzoi cools the whippet a little. I have never heard of them having any negative temperament wise. I haven't been around many though.

I would say they would be fairly healthy, whippets are, and I don't think borzoi have a lot of health issues. Many have the MDR1 gene collies have, because the original cross had sheltie crossed in(Walter Wheeler started the "long haired whippet" farce by crossing whippets with shelties to give them coat)