We've purchased to of these rugs. The plus side is that they're thick and sustantial. Definitely thicker than your standard rug. We had no trouble with this moving on our carpet. The corner weights I bought actually weren't heavy enough for the rug, so that was a waste. 

The down side is the quality control.  We liked our first rug enough to order a second rug a few weeks later. However the second rug came much more frayed and unpolished looking on the ends. There were also a few long stray strings coming out of the sides. I was disappointed considering the price. The rug is too large and cumbersom to return so I'll probably just end up trimming it, but it's a shame it didn't come in the same condition as the first.