So on the fence. There are many situations where they are useful, but there are also many situations where they are insufficient. The problem is that you don't really know until you get them and try them. However, they are bulky to pack in a car. They are awkward to get in and out of. They are dirty after use, which would be nice if that was the situation when they were working. But when they don't work, one tends to resent all the fuss and crap. I'm afraid I think they'll go to my next flea market and we'll stick with the chains.