From training... i'm almost always in some type of muscle pain and have tried MANY methods of relief. I discovered Icy Hot as being one of the best out there. I was using the gel for many years, and it does leave a lovely smell on your hands and is a little greasy. So i was thrilled when they came out with these patches.
They are very easy to open and apply, and you can wear them when you sleep as well. They last for about 3 - 4 hours and a little afterwards... but you can tell after 4 hours it's beginning to wear off.
They also come right off when you want them too, and don't hurt when you do so. They still smell like Icy Hot though, so if you don't like that strong smell, then i would go with another brand.