This plasic carpet has tendency to travel. That is the carpet even with the backer cleats moves one way today and another way the next day. I've had to use screws thru the plastic carpert to keep it where I want it
I love these Flat Pile Carpet Chair Mats that Staples sells because they last a long time and they protect the carpet and make the chairs glide in back and forth from my desk much easier.
I have had this mat for a couple weeks now and it is doing quite well so far. I like the fact that it does not have the sharp pointy spikes on the bottom but rather the flatter jagged edges. I have it on a thicker style wool rug and it stays in place nicely and also does seem to stay pretty rigid after sitting in my chair for a long time.