I have a brand new mega 25 tohatsu i just picked up other day and i have about a hour of run time on it.i got to looking at the lower unit after i took out other day and i noticed the impeller doesn't come with much of a leading edge to it.the motor flat scoots my 18 48 blazer gpsed it making about 35mph down river.i was wondering if a small sharping job would get me a little more as my old motor always gained a solid mph outta a fresh sharpening.its a aluminum impeller so a no it wont hold a sharp edge after a little bit of run time but i have a score to settle with a old buddy of mine on the river and i was wondering if a sharpening and polishing on the impeller and liner and a little grate work would be worth the effort to gain a mpg or two.he running same motor except i have power trim but he is in a 2ft shorter boat thats lighter.i can get him a half a boat length on holeshot but then he drives around me and puts about 2-3 boat lengths on me and stays there.with my trim and can start reeling him in a little on a long straight stretch but i when we make a bend then and gotta get out of them a bit he pulls back out on me.i not looking to outrun him every time but one good trip a doing it would be great.appreciate any thoughts or ideas.here a few pics of what impeller looks like