I've decided to go with a Trijicon Compact ACOG, but I'm not sure which magnification to get.  I know that I want the red dot reticle.  So that leaves me with 1.5, 2, and 3, with different exit pupil sizes for each.  I want it to be good for CQB and also for shooting accurately at 100 yards.  I think that rules out the 3x, because the zoom may be too much for CQB.  The 2x sounds good, but MIGHT be too much zoom for the CQB.  My local dealers dont have any in stock, so I don't have a chance to look through any.  Sooo...which zoom would be best, and should i get a larger or smaller exit pupil?

BAC will eliminate any problems with having too much "zoom"  Us both use open and when you are moving the gun on target, you will see the illuminated reticle and the unmagnified target.  When you place the reticle on target and/or the rifle slows down, your brain will automatically zoom in to use the magnified view.

What is BAC?  I'm pretty new to rifles in general, and I've never used a scope before, so I don't know a lot of terminology.  Would you reccomend an ACOG or Compact ACOG?  

BAC is Bindon Aiming Concept.  It is basically your brain combining the unmagnified view of the target with the view of the illuminated reticle.  It enables you to get the speed of an unmagnified dot sight, and the target idenification of a magnified optic.  Now how close it comes to speed of an Aimpoint or an Eotech can be debated for years.  The same can be said for target id, that a higher power scope will be better at target ID instead of just 3.5X, or 4X, or 5.5x of any of the full-size ACOGs.  They are very good optics, and the price shows it.

As for compact or full size, it really depends on what you are doing and wether you have a carry handle upper or a flat-top.  For the price difference, it is not that hard to step up to a full size ACOG, in my opinion.

For all your questions, I refer you to the tacked topics at the top of this board.

for 100 yards or less CQB, a 1.5 or 2x is just fine.

I use a 3x out to 500 yards, but's that is stretching it just a little.

Forest has used his 3x compact Acog on a CQB class and it worked great, even at 3 yards.