Never flown a 150hp Decathlon, but I have a 180hp Super Decathlon. I predict you will have a blast. Though it doesn't have flaps, if you pull the power to idle on final and slip it hard it it comes down like an elevator. I like 75 mph for speed on final when I'm doing three point landings, 80mph for wheel landings. You'll figure out what works for you. You'll have to adjust to the view out the windscreen. You are used to the sight picture of sitting off to the side. Now, you'll be in the center of the airplane. Steep turns to the left will look the same as steep turns to the right. Straight down the runway means the bar in the center of the windscreen is right on the stripe. If you keep the nose straight on landing, it's very tame. Have fun!