I am looking to build up an upper using BCM's 16" stainless barrel and BCM upper receiver. I want to go with the Daniel Defense 9.0 Lite Rail, but I am at  a crossroads with the FSB. I cannot make a decision between this and this. Cost is a wash, as it's about the same price to send the upper to ADCO for the standard FSB install as it is to buy the ARMS product. I understand the standard FSB will be much more secure, but the ARMS FSB  can be collapsed for optic use. I am looking for opinions or pro's and con's just in case I am missing something. Any and all suggestions would be appreciated.

Thanks

go with the mils spec bcm FSB. no prb using optics with a fixed fsb

+1.

If a standard fixed FSB is an option, it's the option I'll go with, every time.

Thanks for the reply.
Can I ask why? I see an awful lot of rifles with some sort of folding FSB/GB, so people must like them. Right? Other than the durability issues, are there other issues to be concerned with?
Thanks

A fixed FSB is cheap, durable, and gets in the way of nothing. You can't beat 'em.

Some don't like them with low power variables.  If you run a scope at about 3x or higher, you won't see it at all.

I found the fixed FSB to be distracting, but it was not so bad I couldn't shoot around it.

I prefer the folders to reduce that distraction though.

Thanks for the reples.
Anyone else?

i have no choice but to use a low pro or a folder because my scope sits about 1/8" above my KAC rail and the view is totally obstructed with a FSB.  i like to have my scope as close as possible to the bore centerline for accuracy reason.