The LIQUI-TECH products have been around for a while, you usually see them sold at car shows. I used to use their sealer (Finish First), and many compare it to the Liquid Glass product. It really isn't too bad of a product, but I haven't compared it to the stuff I'm using now.
I used the metal protector/sealer on my S.S. firewall in my street rod and it seemed to hold up fairly well.
I also tried their glass cleaner, but found it a bit difficult to use/remove, so I stick with I.G. (my current favorite). When I used the Finish First sealer I also used their QD (Finish Fast), which seemed to do OK also (worked fine in the sun). I haven't used it since I switched to S&W, S&G, and Quik Shine, maybe I should dust them off and do some product comparisons with them.