A little help needed.....

[RomanCatholic]

Here is what I have.

LMT 16" flat top upper.
LMT lower with 6 position stock.

I ordered an MI 2 piece handguard. (http://www.aimsurplus.com/acatalog/Midwest_Ind._2_Piece_Carbine_Handguard.html)

I also ordered a tango down fore grip because I have a tango down grip on the lower and I like the looks of the tango down fore grip.

I am thinking of buying an AIMPOINT Comp M3. Does the AIMPOINT mount directly to the upper?

Would a flip up rear sight work or would a permanent fixed rear sight be a better option?

Any suggestions would be appreciated.

[MrMurphy]

Aimpoints require a mount. LaRue makes the best out there.

A flip up rear works better with optics, which is why they're the backup. If all you run is irons, get a fixed rear.

[Big B]

Get the Aimpoint COMP M4 it does not require a mount and it's the best optic Aimpoint makes.

[RENEA]

Ditto with the LaRue mount. Mark LaRue makes the best kit in the industry, hands down.