I have been getting lots of tight muscles lately, and this just quite honestly feels divine on those stressed out muscles.
It took me YEARS to get on the weighted blanket train, and I wish it hadn't. I have never ever slept or napped so well as I do with this blanket. There is lots of science behind it (check that out here) which always gets me going!
If you're going to invest, go for 10-15% of your body weight. I weigh 125lb, and have a 15lb blanket.