Sig ist a very good gun.
I`ve shot the duty P6 from a fellow at the range a few times, who is with the german police.
Although I have small hands and therefor like tinner grips, the Sig`s grip is to small I find.
If you go for a Sig, try to find a 220, 226 or 228.
Due to the light Metal frame, most of the Sig`s are light for carry in CCW.
Ruger I have never tried, but if you are looking for something around $ 400,-, why not go for a CZ75, in what version ever. Very reliable pistols. They all have samll grips and double row Mags.
They are accurate and very durable. Spare parts are no problem, aswell as lots of tuning parts.