I don't mind doing the occasional headshot but just like my photography, I prefer the body to be included in the expression of my renders.

I don't want to sound rude but I think that there are so many face framed shots around because it's much harder to pose the complete package yet at the same time facial only renders can be a very tough sell that either look astonishing or very bleh. I would however, be interested in using high poly shoulder up models as long as they're fully rigged and the expressions are thoroughly realistic.