I've had two Sigmas (a glutton for punishment, I guess). Personally I like Glock in many calibers, but not in .40. XD has them beat all the way there. Ruger makes a nice one now, the SR9, but no .40 yet. Beretta 96 is a nice one. Taurus has the PT-101 that holds a whole lot of rounds and is very accurate, but it's heavy compared to plastic guns.
Sigmas have dastardly triggers. I know lots of people who have made excuses for the triggers, but no one really likes the trigger. It wears you out and reduces accuracy. They would have had to do a whole lot of work on the trigger to improve the Sigma series.
Enjoy life a lot and go to a range where you can rent some different models.