Well, I have all three in question. And IMO each is very different. Not sure what you want to know other than the usual: trigger pulls differ, grip handles are shaped different, etc. If I had to pick the better of the three (for me) I'd choose the Sig first. I purchased the XD9 (Tactical model) for competition use. I thought about using the P99, but the trigger pull made that a quick No way decision. It's a tough call because you are comparing quality firearms. As far as price, a new Sig is more than the Walther, then the Springfield comes in third. I wish I could tell you one is better and the other is junk, but it's not the case. If you can touch and feel both side-by-side, you should be fine with your decision. Oh, I won't tell you which of mine is more accurate, that would really confuse you more.