The 8" clamp is very rigid, and good care was taken in the finishing process of the steel plates. The peened-on support plates are beautifully done, and I have only found one location on the rim of the metal where it may cut you. However, this was not part of the design, but likely from USPS.
The design of the clamp is very well thought out. there is a left and right handed threaded rod, that is a good bit larger in diameter than the Kant twist. Speaking of which, this clamp is superior in almost every way to the Kant twist clamp style. the metal is thicker, all pins are in compression against the support walls, so no tearing out through the wall- nicely done.
it always surprises me that it can open to 8" while maintaining such a short threaded shaft length.
The main thing I could see as a need for improvement is on the ends of the threaded shaft. The end where a socket would fit over is a bit too rounded. I could see after a few years of good use, but I would like to see a process that can get a sharp(er) edge on the corners of the hex that fits into the socket.
On the other end, the (hardened, I believe) circular handle is nicely machined, but the hex shaft pressed into it needs some work. The ball detent is only on one side, where the hex slot it fits into has 2 divots. not only having a single point of contact to keep the handle from falling out, but the steel piece that surrounds the handle is too loose. Again, after years of use, I could see the hex hole being bent out a bit, but a new part... it should have a tighter fit. Also, the rim around this part seems to have a lip that doesn't need to be there; maybe in the pressing process, the press missed the whole part, and left the open end more flanged than it should be. Also on this piece, I would like to see sharper edges on the hex , like on the opposite end of the shaft, so that someone could use a wrench if they chose to.
Overall, the handle slips out far easier than I would like it to.