It looks like you made use of some scraps CGC! Very nice work. I have to say that from my experience with forming rings, the slip rolls are the most simple way of producing a ring (in a very quick manner) that is perfectly round. They only work on smaller rod diameters and thinner flat stock though. Also, in order to remove the flat spot left on the trailing edge during the forming process, you need to alternate which end you run through the rolls. This is assuming you are like me and want to cut the rod to the correct stretch out in the first place so you don't have to cut the excess rod off later. I have never seen the compact bender used as slip rolls (very clever idea!), but I would think that adding a speed handle of some sort (or possibly a motor) would make that setup much more efficient. It sounds like you're interested in that conversion after seeing the video, so I thought I'd mention that. Feel free to call me Captain Obvious if you wish. I've been called much worse, believe me!

I used a full size version of that compact bender years ago to make 14" ring from 3/4" solid round stock. That was back in high school, and needless to say the results were less than perfect! I used my eyes and followed a chalk line circle that I drew on the floor, and much time was wasted heating and hammering to make it round, smooth, and perfectly flat! Bend it a little, lay the ring over the chalk line, mark where it needs to be bent next, bend it more, check it again on the floor, etc. It did come out round, but never quite flat! Only took like 5 class periods to finish it too!