Both are well made, reliable guns. The Ruger however has a much better trigger in my opinion. In fact, the Sigma has the worst trigger I have ever seen on a gun. However, I've spent some range time with a Sigma and it is very easy to shoot very well.
Bottom line, both are good guns for the money. Pick the one you are most comfortable with. Even with the trigger on the Sigma, if you like the gun and you can live with the trigger, it should last a lifetime.
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