I received my 17HMR Hunter from them last week and the rings were missing. My FFl called Ruger and they sent one ring. They are now going to send another. The manual send with the gun was for the Blackhawk and not the Single Six.
I know Williams' had a bunch of these a short time ago and generally will be less than Davidson's. (you pay a bit for their "gaurantee" which is pretty much handled by the manufacturer anyways)