Isn't the Tavor the standard offering these days or are they still issuing M4's ? My point being, will you actually get to use an ACOG whilst you're over there ?
I have 3 ACOG's. The TA31RCOA4/ M4 and TA01NSN.
I prefer the TA31RCO Chevron reticules for snap shooting over the TA01NSN cross-hairs, although I'd imagine that a 4x optic is the last thing you'd want for CQB.
I don't have the piggy-backed RDS, so can't comment on usage, although the 'iron sights' on the TA01NSN appear to be fairly useless IMO.