Yes, my lens is a 14mm, aspherical lens, technically its an "ultra-wide angle", not quite a "fish eye". If you get say, a 10mm lens, you will get much more distortion. Like these (not mine):
What can happen with fish eyes though, is you might get vignetting, depending on the lens. Example:
In which case, you would have to crop the image. I prefer "full frame" lenses, but you start talking big money when you are looking for "full frame", like $600 and up, which I guess isn't bad when you are talking decent lenses...
Bart