I've owned a Sigma SW9VE since 2004, and love the thing. It's been solidly reliable, and very accurate - usually I pull down and to the left because the trigger pull is kind of heavy, but I prefer the heavy trigger. I find the longer the trigger pull, the less chance that I accidentally discharge the gun. It reminds me of a double action revolver trigger pull. My trigger was never gritty or anything, always smooth with a clean break. It did get smoother over time though.
Good choice for a first gun, it was my first gun, too!
The best part is the S&W warranty - if anything goes wrong, send it in!
You may read some complaints about the Sigma, and like any pistol there are lemons. The early models of the Sigma had issues, but those have mostly been worked out. However, it did tend to create a bad rep for the poor little Sigma when it was first introduced.