The GM OEM valve is there to eliminate drone when engine is in Active Fuel Management (AFM) mode.
http://www.rmacadi.com/rpress/wp-content/files_mf/borlasilveradoproductsummarysheet.pdf
Looks large in the pic but actually it's not that big. They are aluminum brackets, lol... probably don't weight much more than a stainless clamp. I didn't notice much if any HP gain with it on so I removed it.
Anybody know the part number for the chrome middle lower portion that's on the 2014 LTZ front bumper (I think high country may be the same piece). It has the tow hooks on each side of it. You don't get it in chrome on the LTZ Z71.
2014 GMC Sierra CrewCab chrome window trim.
The prices are basically the same at most of the online retailers I checked. Free shipping is probably where you will see the difference.