Sig makes one of the best DA/SA handguns in the world. They are a kind of gold-standard, and their stock trigger is smooth, crisp, and clean (especially after a few thousand rounds).
The real deal in Sigs is the Certified Pre-Owned market. These are well used handguns that go back to Sig for a factory refinish, and a full replacement of parts that experience wear (barrel, springs, etc.). They come back almost indistinguishable from a factory-new handgun, but have the buttery feel of a well worn piece.
The Sig Short Reset Trigger (SRT, not to be confused with their Short Reach Trigger, which does exactly what it says: shortens the overall trigger reach) is, to me, an industry standard for the DA/SA platform. It is a short, crisp DA with an ~8lb pull, and a startlingly short reset with an equally startlingly light ~3.5lb single action. The thing is a machine.
The new E2 grips are not everyone's cup of tea, but they have the exceptionally grippy feel that the HK P30 and Walther PPQ have, which I am a huge fan of. The grips are slim as can be, and offer a great hold.
For a new Sig, I'd lean towards either an M11A1 (their remake of the P228) or a P229 in 9mm. Mine is a .40 cal P229 that I converted to 9mm with an P228 slide assembly and locking block, giving me the best of both worlds.
Fantastic handgun.
I carry my Glock 19, though, as it is slimmer and lighter.