I'm in the process of building a 16" Dissipator with an ACOG and a Larue 12" FF rail system.  

I already have an ARMS #40 BUIS, and need to decide what front flip-up sight to install.

From reading some threads here, it appears that the PRI sight is the most stable, but I'm thinking it might be more convenient to simply add something like the Troy flip-up sight to the Larue rail.

Is the Troy sight stable?  Will it work with an ARMS #40 flip-up rear sight?  Is there another option for the flip-up front sight that would work better?

Thanks in advance.

The Troy and KAC are the only two out there that I would really consider, and the Troy is the better unit. Heck, the Troy is the only one sturdy enough to consider using for a primary sight. It'll work with an ARMS #40, and will be 100% stable on the LaRue rail...

-Cap'n

I am planning on using the TROY front with a #40L rear on my CAPN_COPY carbine. I prefer the default small aperature. Plus it keeps my weapons consistent.