I ordered these from amazon and they had some decent reviews, nothing that mentioned the difficulties I had. In fact I think my review was the worst one but I wanted to be honest for someone who didn't have the ability to fix them. That said, as someone who CAN fix them I think this is a steal where you are getting the materials of a $20 unit at a $5 cost.
Below is the link and if you click and buy here I will be getting a few pennies so full disclosure.
I don't mention it in the video but if you get one where the thumbscrew has stripped out just rotate it around, drill and then tap the body to relocate the screw. Just make sure you drill it just slightly lower than the original hole.