I have the HS720 also, about 5 years old. I replaced the auger paddles this year for the first time, they were very worn. The scraper blade had enough left on it so I was able to adjust it down to give 1/8" clearance between the the paddles and the ground, which is the spec in the manual. It is a pretty expensive maintenance item as the paddles cost me $65 and the scraper bar would have been another $35. Now that I know how fast they wear I will keep a closer eye on them, the machine performs like new again with the new paddles on it. It was very easy to do but much easier if you get the machine off the ground to work on it. I used my motorcycle lift. I wonder if there is a cheaper source for these parts. I'm sure I pay full retail or more from my local Honda dealer.