They work as advertised. They make the cleanest cut possible for a generic cutter like this. However, I think the shears could be improved with a tighter cutting radius. If the cutting hook was smaller, I think it wouldn't crimp as much as it does. I used a 5.56 blue dummy round to round the crimped cut afterwards, and that practically addressed my issues with it. This was for 6AN line.
The 3 piece that seals around the PTFE lines is clean. That makes this an order of magnitude easier to assemble than versions made for rubber hoses. Count your connections before buying! I had to order again because I forgot two or three connections.
I originally did my race setup without PTFE lines, and those rubber/stainless braided hoses stunk up the garage like nothing I've ever used. After replacing everything with the PTFE lines, the garage smells nice. Worth every dollar, and the headache-free smell of the garage makes it worth it too.
Great product, fast shipping, great customer service. We will be ordering a few more things soon.