I bought the Bower (aka Rokinon, Samyan, Pro-Optic) lens in April. I used it a couple times but was having an issue with the aperture ring staying in place. In June, I wrote to Bower that I was having an issue with the lens and they sent me a brand new replacement (I had to send back the old one). I used this lens one time since I got it. It’s an awesome lens, but I upgraded to the Nikon 14-24 f/2.8. There is really no reason to keep this lens, so I am offering it for sale.
This lens is for Nikon, and has the autofocus chip. Do note, this is a manual focus lens. This lens is used by many astrophotographers.
Here is a a photo I took with it: