You could do a search on "Hiniker" and get a lot of information. The consensus seems to be that there were a lot of design problems at one time, but they have been fixed. I've looked over the C plow and considered one, but it just doesn't seem worth it to me. I would only use it in the "backdrag" position for maybe 2 or 3 passes on any one job, just far enough clear an area for the truck. With the C plow I'd still have to turn around. There would still be snow up in the frame. If I had a lot of backdragging, I would think a backblade (on the back of the truck) would be better. Then you could just back up to the garage (house etc), scrape forward with the backblade a few feet, back up again and you're ready. Faster with less snow built up in the framework.
However, just my opinion. Someone who actually owns one could give you better insight.
I'm sure the C plow has its applications, but it seems they would be limited. If you do a lot of loading dock work it makes sense, or maybe narrow drives that end at a garage, but for overall snowplowing, I'd favor a v-plow of some type. You will save more time with this style over the C plow in the long run.