Well I just got back from testing my new improved impeller that was worked over by LT. It works great! I did the work on the grates myself with the bench grinder, not as cool as the mill but sufficent. Lt cut the new edges on my impeller so they are sharpened at the proper angle and of the same height. Before my cruising speed was 24 mph @ 4200, now 24@3600 or if I prefer 29@4200. Keep in mind that the before performance was from a basically new impeller, not rounded or dinged up. Very much worthwhile, Thanks for the help LT!!