Chris. I think you are a little high on your estimates on the Glock and Sig. I have seen them at much lower prices, and if you will settle for a factory rebuilt gun they can be bought almost as cheap as the Ruger and CZ. CDNN has a new Sig P220 for $579.99, or a P245 for $589.99, or a Glock 37 or 38 for $399.99. A factory rebuilt (like new) 22 or 23 for $339.99.
You are right about the CZ, it is a well built pistol, and as tough as a Marine First Sgt. I don't have much experience with the Ruger, but have fired one several times, I don't think either will compete with a Sig for accuracy, and doubt that the Ruger will perform flawless for the same number of rounds.
Bottom line, it is all about what you feel comfortable with, and have confidance in. When my butt is on the line, I feel much safer knowing I am packing a SIg.