yea i get yea-but those are replaceable at a low cost in a min-with this you would have to throw away the whole main frame...to be honest with you any good tattooer will look at that and stay away from it at those prices. These crank designs has been around for years and work great. And have been done with springs etc. And the simple ones work the best at a much cheaper price with easily sourced replacement parts.The problem with yours is if it breaks from a drop or wear you have to replace whole body which would be fine if it sold in the 50-75 price range. It would be considered a disposable machine. You can get these crank style from china now that are well made and cost 35-50. I do like the idea of the back as it will keep the crank centered with no side sway and the crank bar damping is nice. And being able to use a hawk grip is sweet as well. So I would say make it these way as at a cheap disposable price and one with a pivot pin and bearings for the price your asking. Maybe you could print me one out with the pin/pivot back style.