The P250 is a double-action only handgun. I own several of them and absolutely love them, but they do have a long, but fairly light trigger pull. They were designed that way, there's nothing you can do(or should do) to change it. My advice is to shoot it and see if you can learn to live with the trigger pull. It's not for everybody, though. The 250 does have it advantages. Sig accuracy and reliability, ease of maintenance, and easy on the hand while shooting. It probably the most versatile handgun platform ever made. I find it to be the ideal CCW.
I would be happy to answer any questions. you might have. Hopefully, you can enjoy the 250 as much as I do. Here's a photo of my 250 line-up.