I'm not sure what other reviewers are doing with this mat and maybe I just had low expectations but this seems perfectly suited to for its purpose. I have a heavy elliptical (Schwinn 438 - which is great by the way) on new carpet with thick carpet padding.
I was careful placing it and didn't try and drag the equipment across the mat to straighten it (as I had read reviews about the mat tearing) but it does exactly what I would expect it to do. It protects my carpet from sweat and limits the amount of carpet fibers that can get into the mechanisms. I thought it might scoot around a little as I use the machine, but that doesn't seem to be the case either.
I'm glad I didn't spend more money on one of the other options, because I don't really see the need for anything different.