Does anybody have hands on experience with this lens. I was searching for some feedback, but found only chit-chat.

I have a Nikon system, and so there are three possibile choices for a full frame fisheye lens:

Nikon 2.8/16
Sigma 2.8/15
Arsat 2.8/16

The Arsat lens is cheap, but isn't AI connected and in top many complain about the mechanics. So far seems that the Sigma gives the best price/performance ratio, supporting D metering, but since I never owned a Sigma lens, I would need some feedback about this specific lens, or Sigma lenses in general.

Many thanks