I don’t have one, but it’s on my list of “I want one of those things”.
Good article on 458 SOCOM; I’m going to think about one, too, but I also have a Barrett .50 BMG w/ BORS. The 458 would nicely compliment my Beowulf.
http://www.military.com/entertainment/outdoor-guide/ar-hunting/rifle-review-458-socom.html
I get a weekly newsletter from a civilian specops company who sells the 458 SOCOM and a lot of other ‘special stuff’. Next one, I’ll forward it to you.