The S&W Sigma series is a Glock knockoff. So much so that Glock sued S&W for copyright infringement, and won. Google it. It's an OK pistol for what it is, but it's not an M&P or a Glock. For the price, it should serve you well for basic needs.
Pros:
Eat anything you put through it with little to no hick up.
Great in the hand when you put the Hogue Slip on finger groove grips.
Easy to maintain.
Fairly light even when loaded
Cons:
Terrible trigger
bad accuracy. (Well, you can keep it within the body on a silohuete (sp) target. its attributed to the bad trigger)
Terrible Trigger!
When shooting a lot with the .40 S&W your hand will hurt a little bit. This one is a bit nit picky but something to mention.
The trigger is most peoples complaint. Its good for a 1st gun. I know because it was my 1st gun. Tends to let you know what you do and do not want in your future pistols. Get a CZ-75 next.