I strongly prefer the TA11 3.5x over any of the 4x ACOG's because of the longer eye relief--especially important with a 6.8 mm.
Also, ask yourself what you are doing with the optic; for most uses in the 0-300 range, I find an Aimpoint RDS in LaRue mount in conjunction with an Aimpoint 3x magnifier in a LaRue LT649 to be the best set-up. I also find the 1.1-4x S&B Short Dot, 1-4x NF, 1.25-4x Trijicon Accupoint, and 1.5-5x Leup to be more versatile than the ACOG in the 0-300 range. Mini RDS's on top of ACOG's are NOT user friendly--I'd avoid them if possible...
Also, ask yourself what you are doing with the optic; for most uses in the 0-300 range, I find an Aimpoint RDS in LaRue mount in conjunction with an Aimpoint 3x magnifier in a LaRue LT649 to be the best set-up. I also find the 1.1-4x S&B Short Dot, 1-4x NF, 1.25-4x Trijicon Accupoint, and 1.5-5x Leup to be more versatile than the ACOG in the 0-300 range. Mini RDS's on top of ACOG's are NOT user friendly--I'd avoid them if possible...