I am not and never was a fan of fisheye lenses and that includes Hasselblad and Nikon. When I tried them I ended up with photographs that showed the tops of my shoes!
OP, for round I shoot lots of circle fisheye. But once in a while I will crop round if it is best for the pix. If I had a view cam I'd shoot some round photos. I like shooting close to people and circle fisheye demands you are 3 feet or less to get a good shot.
Pinky, The Grove L.A....Candid.
The circle fisheye is hard to shoot with. Sun and feet get in the photo and comp is an issue. But when it works...it works!