I ordered a Sig 556-SWAT, and hopefully it will be waiting on me when I get home from this deployment. I don't have a scope for it yet.
I have never used a EOTech HGS but I have heard their praises sung. I have used 100yd. Mil dot scopes (like an SKS scope) for medium range shooting and I am pretty proficiant.
In ya'lls opinion, which optic would be best suited for accurate medium range shooting. I am aware that for the reasonable price of $400-$500() you can add a 3X-4X magnifier onto the EOTech. It may be slightly harder to get a quick sight picture on a fast moving target with a scope, but your shots are likely to be more accurate. If you can't get a sight on your target, you can't hit it.
p.s. I'm hard pressed to try and keep it under or close to $500.