I would check out either the ARMS 40 or the Troy Industries BUIS. For a CQB setup I prefer the older ARMS #40, not the #40L. The older 40's are spring loaded and are very quick to deploy. The primary difference between the 40 and 40 L is the L has a lower profile to fit under scopes, but it deploys with the small aperature first. The standard 40 pops up with the large aperature first which is what I prefer.The other option is the Troy. I prefer the Troy's for all other applications. Good, rock solid design. I like the locking detent that keeps it in place once its deployed.Erik