ok im going to but in here for a min if you take a car and advance or retard the time you gaining or losing something your eithe gaining power and losing fuel economy or gaining fuel economy and losing power i no you are talking about the smaller planes but evolution makes a 10cc at the cost of 200 bucks whats the little weight for reliability me personally i still have several glow planes but everything ive bought or built in the last year has been gas i have several .40 and 60 size planes w the dle 20 or vvrc 20 so what there a little heavier they have the power to overcome that