A resurrected thread! I had never heard of these until we were given a few free samples in the Supermarket. I'm afraid they are not for me. I have an extremely keen sense of smell and so disliked the synthetic odour that I had to wash and rewash the bedding to get rid of the smell which I found overpowering. I have the same problem with scented candles and had to leave a friend's house and sit outside with her because she uses those plug-in thingies.....and don't get me started on those smelly,dangly things in cars, beloved by taxi drivers. It's good to know that they do what they claim though.
It's a great pity the right of free speech isn't based on the obligation to say something sensible.