All I can say is sweet. My yard was very, very wet but it needed to be cut. I cut at 3.5" and I was taking at least 4" to 7" s of grass off the top. Even going slow to compensate for the amount of grass I was cutting and getting used to the new steering, I was still able to cut the lawn in 20 minutes less than with my 445.
I was a bit rougher in spots were I have drove the 4520, but the cushy seat soaked most of it up. The deck is simply amazing as it will not leave strips of grass even if you make a complete 360 turn. I could not be more happy!
The power seemed great for this machine and with the amount of grass I was cutting. It was neat to be closer to the ground and able to see everything around me so well.
My only issue so far is the ROPS. I can get close to most my trees but they do get hung up on low branches. They are fold-able, so that might be the answer.