40hp for most people, and almost everyone on this site will agree, is the right hp for the Snow Goose/Scaup boats. It is true that with the power trim/tilt you can tuck the motor in farther (negative trim) and that probably is what is allowing your boat to run without porpoising. But then again, I didnt put wedges on my Scaup and it does not porpoise, unless i'm in the boat by myself with no gear except 6 gal gas tank, battery, and my 280lb frame in the back of the boat. Once I ad another person in the boat, or some gear, it does not porpoise. Truth is the 40hp is the right motor. I am often caught dragging my boat across shallows and over mud/sand so the extra weight of the 40hp is not the right motor for me. The 30hp (2 stroke, not 4 stroke) performs admirably on my boat, even with 3 guys, dog, decoys, gear. There is plenty of power for me to control and manipulate the boat in any sea condition. I hunt everything from the Skagit flats delta to the completely open water of Padilla Bay in the San Juan Islands. So to each their own, and if you want to be safe in your engine pick and make sure you never lack hosepower, spend the extra $2,000 and buy the 40hp. When I run in shallows, which is almost all the time, I dont slow down for the most part. I keep the boat on plane and skim right over the 18" deep water. Occasionally I do hit bottom, which is no problem because I keep the motor unlocked so it will be allowed to kick up. Personally, I would not have the power tilt unless I did the majority of my hunting in deep water, which in that case I would have power tilt. Good Luck