[F22_RaptoR]

The 4 moa dot would probably be a little crisper and easier to see, the 2 MOA would be better for longer ranges, but Since your max is 100 yards, the 4moa would probably appear to be a little more circular and easier to use. (sometimes smaller dots can egg out or deform due to imperfections in your eyes) and the bigger dot will be less prone to that.

ETA

I have an Aimpoint Micro on mine with the 3.4moa dot and I've never had any trouble hitting anything I was shooting at, so I don't think the 4moa dot would limit your accuracy.

 

[GrandmasterB]

Either should be fine. The C-More will sit too high to use your iron sights however, if that is a concern.

 

[Las_Vegas_HK]

4 MOA dots work well on SMG type rifles. 4MOA should have quicker target aqusition. Usually a good bet it to site it in at 50 yards and make minor corrections for anything closer or further..

I always feel that 2 MOA dots are designed for rifle caliber battle rifles, but look at Eotech, 1 MOA center circle and a 65 MOA outer circle.

 

[pb_removed]

To be completely honest, it really doesn't matter. Your adjustment of the brightness setting is more critical than the dot size.

 

[Cossey]

Being that it's a pistol caliber, the either or may be your best choice since it's not going to be shooting anything far. I have a Vortex SPARC on my USC and although it may sit a little high, it's still comfortable shooting using that sight. The red dot is 2MOA on it, and it comes with a magnification piece you can use (I haven't since I don't think I'd need any zoom shooting pistol ammo).