I will most likely get flamed for this but after taking materials courses this is what I have learned:
Lexan is General Electrics name for there polycarbonate resin thermoplastic. They use this stuff to make bullet resistant windows. Lexan also has a high resistance to warping and melting from heat. I am not sure about discoloring, my guess is it wont yellow.
This tube may look cheap but it should work for its intended purpose.
Yes, the rest of the kit looks cheap like the eBay stuff but I paid GMK (from the same web site) a bunch of money thinking I was going to get a nice kit and all he did was provide two dented extension pipes with incorrect bends along with the very crappy eBay like other parts.
