When I was looking at getting an Aimpoint, I found that the Comp ML2 does come with a 2X fixed magnifier option and 2MOA dot.
I opted for the Comp ML2 (4MOA) with LaRue M68 CCO mount on my 10"/SBR Lewis Machine & Tool AR15
http://stores.homestead.com/Laruetactical/Detail.bok?no=184
It is VERY STURDY and with this sight I can hit steel (4") auto poppers at 25 yards - then transition to (stationary) clay pigeons at 30-50 yards
PLUS - I can co-witness using standard MI BUIS. The LaRue mount is slightly taller, so that the co-witness of the BUIS is actually in the lower 1/3 of the optic, which works out very well for me.
I'd like to know how the 2X works (is it better or no difference?) - should you happen to snag one.