Does the trigger feel or act any worse for you than say a Ruger LCP or a DA revolver?
From my experience, yes, the Sigma has the worse trigger I've ever felt. Long, gritty and uneven. With that said, I shot the hell out of the gun and was surprised at how accurate I was with it.
While they have a well deserved reputation for having terrible triggers, I think for the money they are good guns and certainly make a good truck gun.
I think you'll be happy with yours and find it shoots pretty well. As far as ammo, for a 40 I prefer Speer Gold Dot HPs in my Glock. WWB seems like it runs pretty well through the Sigma as range ammo.