Well, I purchased the cheap Guohuo GH 6 x 12 film back. It was made of plastic and while it didn't appear very durable, it did appear well-made with prescision.
Despite that, the knob didn't appear to be glued or attached as it was incapable of rolling. I had to epoxy it myself. Which was a relatively painless endeavor.
After that, my first roll was completely fogged on the frames. I figured it may have been from where the darkslide comes out of the holder. There is no light trap material there.
The next two rolls I tested proved that. But the tests also proved that it did leak quite a bit there. But also leaked while the darkslide was coimpletely closed without exposing the frame......
Also that light leaked at other places where there shouldn't be any leaks.
The seller claims it was a bad batch from the manufacturer. I am going to go with the Dayi and see how it works out for me.....