I purchased this for a lightweight AR build, as I wanted something light and minimal, and this pretty much fills the bill.
It's well made, weights 3 oz., and installs easily. If you're looking for a lightweight minimal stock, this is an obvious choice.
The only cons are that you're essentially spending $69 for a tiny piece of aluminum with a hole and a tightening screw in it. This seems like something that could be produced FAR more cheaply, and I'm sure we'll see the industrious people of China introducing something similar for $19.99 not too long from now.
Also, if you're a larger person, a .3" deep buttstock is not going to provide sufficient length of pull for comfort. This should be completely obvious given the product and its description, but on the odd chance you're a large person who's overexcited about your next build, you might want to add a rifle length buffer tube before it shows up at your house and you're thinking "What is this? A buttstock for ants?"
That said, those are the only quibbles. The product is well made and made in the USA, so if you need a product for a lightweight build, this is a solid choice.