I bought this for my husband after I started using one myself. It's not that easy to get on, and it pinches after a while; I definitely wouldn't find it comfortable under clothes, so I only use it at home when sitting at my desk. But it does pull my shoulders back and down, helping me to allow my neck to lengthen properly. I'm hoping it will eventually help loosen my neck muscles and reduce headaches. That hasn't happened yet, but I do think it's helping somewhat. Worth trying if you have neck and shoulders issues and sit at a desk a lot.
I like this yoga mat quite a bit: it provides just the amount of extra padding I wanted for my knees. Love the color, too (I got the purple)! The only thing I don't care for is that I'm finding that my hands and feet slip much more than they did on my old mat, so I need to use yoga gloves and socks, which can be annoying. It also needed quite a bit of airing out when first purchased to get rid of the new plastic smell.