it depends on the camera you would be using.. On a full frame, in my personal opinion 10mm is too wide.. however on a 1.6x camera, 10mm makes it equivalent to 16mm which is very desirable wide angle..
Personally I like extreme wides and fiseyes both..
With a DSLR and Panorama Tools freeware, it hardly matters nowadays.
You gain detail introducing fisheye distortion into a rectilinear picture and lose detail making a fisheye straight. So an ultrawide angle is better. Will show photos to demonstrate what I mean later this afternoon.