Not true, In my experience, a 61 4-stroke will run considerably longer on the same amount of fuel as a 46 2-stroke.

A 46 LA will be lucky to turn a prop at 10,000 RPM. A 4-stroke would turn a bigger prop just a little slower, let's say 9500RPM

So in one minute, a 46 2-stroke sucks in (10,000 x .46ci) of air, or 4600 cubic inches of fuel mixture. A 61 4-stroke (Which only pops once for two revolutions) will suck in (9500/2 x.61) 2897.5 cubic inches of fuel mixture. That's about 2/3 of what the two stroke is using, and that doesn't take into account all of the unburned fuel that a two stroke spits out on every single stroke.

At 2/3 fuel consumption, a 10 minute flight with a 2-stroke becomes a 15 minute flight with a 4-stroke.

Another way of putting it is, If you burn 4 gallons of fuel per month, that's 12 gallons in 3 months. A 4 stroke will burn only 8 Gallons. If you buy fuel at $15/gallon, that's a $60 savings in 3 months.

But don't let the facts stand in your way.