What I hear the most about Gulfstreams compared to Falcons are the handling qualities. I've never flown a Falcon but I hear they are a blast to hand fly. The Gulfstream is like a truck in comparison. They have a much slower response time, especially in an unusual attitude recovery. It takes a lot of rudder to lift the wing up when you need it. I personally like the 550 better than the 450. The wing is larger and more efficient. Very low approach speeds at light weight. Easy to fly.