Eotechs are great. You might consider the 512 that uses AA batteries rather than the 511 which uses N. It's a bit longer but it's undercut forward so it can still be mounted forward enough to allow a BUIS to go behind it on a standard top rail.
If you're looking at possibly adding more such as a maginfier, look at the Eotech 517. It has the buttons on the left side for easier access and the mount raises it 7mm so it can be mounted farther forward over the handguard.

 

My SWAT has the dinky flip up one.

 

Heh, at least at the ripoff price for CA, I got both the holo and the regular sights.

And I still have to wait 8 more days to pick it up.

I need to move to a free state like TX.

 

If everything I read is true you'll be taking those off. The Sig front sight is not compatible to any "aftermarket" rear sights because of it's short height.. After reading some comments about the sig holo, I'm glad I bought a stripped down version. Of course peoples opinions are like .....

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