I original bought the 'universal' cutter because I wanted to accurately cut some carpet ... and wanted something that would produce a better and more accurate result that my previous attempts with a Stanley Knife.
I tried the 'cutter' on 2 grades of carpet, the first, a wool carpet with a fabric backing worked fine ... if a little slow. I knew that I was pushing it a bit when trying to use it on a rubber backed coir mat, so was not surprised when it failed.
Many of the reviewers have mentioned the slow cutting speed, to a certain extent that can be a good thing as haste often leads to (costly) mistakes.
I have also used the cutter on plastic and thin rubber matting, as well as on cardboard and it worked well.
I think that the accuracy of the cut on the carpet probably justified the expense of the tool, and was cheaper than getting a carpet fitter out ... and I now have something in my tool-kit for the future.