Joining this conversation late, but I think the 1000 is the way to go as it can be Dyna'd and you can get parts. The 1200 black box is no longer made. In reading other posts, I bumped my timing ahead about.... a little bit, yep, just right, to help with the ethanol blend. I have noticed a bump in mileage. My plugs are tan, but she knocks a bit when taking off. I was thinking.... scary, I know......... it wouldn't take a lot to set up a vacuum to bump the timing plate a degree or two and then let the weights do the rest. I have read that messing with the spring advance usually results in breaking it as the metal is brittle. The corn is here and we're stuck with learning to use it.