Bought a DYT4000 (18.5hp) to replace tired LT1000. Thought it would be fast but after 2 mows, not impressed with larger hp, seems to take just as long. SHould have sprung for GT 5000 with larger deck. My neighbor said, just take it back and get the bigger one. Will Sears really do that?? The tractor has 5 hrs on it. I'd be willing to pay "restocking" fee or whatever. Anyone had any first hand experience with this?