I'd have to say the first Sig I bought was because that was what the FBI was issuing at that point, and I had aspirations of being a feeb. 229 in .40 caliber. The gun pointed well, and set up just right for me. I liked it better than the Glocks because it seemed to handle the recoil better, when shot side-by-side.
The 232 fits my hand well, shoots pretty accurately. Seems to be the go-to gun these days for concealed carry.
239--ditto. I even like this better than other sigs because of the small size. the 9mm version is pretty tame to shoot, and the single action is one of the better ones that I've messed with. Too heavy for pocket carry, though.
220-points great, best double-action pull out of any gun I've owned, and more accurate than a $300 used gun has any right to be.
My favorite is the 229r in 9mm. Depressingly accurate, fits the hand well, points great, etc.
Ergonomics seem to make these guns. I think their weight helps manage recoil very well. I also think they are wonderfully accurate.
I only wish there was a manual safety like on the USP's. Barring that, I love the decocker and SA/DA set-ups on Sigs.
It just seems like SIG turns out a quality product all around. You know what you are getting when you buy one.