Pros/Cons of Red Dot Sights

[Skeeterbait]

If you have really good young eyes then you can use the 2moa.  But it is really meant for precision rifle and pistol shooting.  A 4moa for a shotgun is plenty small enough and easier to pick up, especially with older eyes.

[Frank G]

I use 2moa on all of mine, but that's just me. A 4 would be OK if your just going to use it on your "T" buster. If you plan on moving it to a rifle/big bore handgun for deer, would stay with a 2 moa when your working out to the 60 + yard range. 

[Hognutz]

A 4MOA will cover a 4" round at 100 yards. A 2MOA will cover a 2" round at 100yards. At 50 yards, it is half of that. At 25 yards, it's half again. So a MOA dot will cover a 1" spot at 25 yards. This makes a 4MOA dot seem like the one I would, and do, use if given the option.