I used the cavision box with it and it worked fine.. I had a slight back focus problem (i know it doesnt make sense) way back when that I emailed Century about but never got a response.. it went away though as soon as I took the ring off and didnt come back when I put it back on, so it may of been my installation error, like I may of tightened it to much and it actually deformed the barrel.
Anyways, the good thing is that it had a macro lock so the ring had a hard stop point. It worked with the chros follow focus and the Clairmont focus gear. Clairmont however make's there own ring for $80 that works with most gears, but the Century is markable so you can mark lens points, if for some reason your focus knob isn't markable.
I might of bought it if it was a little cheaper, I still cant figure out why it costs so much.. but it was a good unit.
Cavision emailed me though letting me know they are designing an entire follow focus system for the DVX that is much cheaper than the others, I will try and get one for review once it's ready.
