4-STROKES HAVE MORE TORQUE AND DON'T HAVE TO TURN AS MANY RPM FOR POWER. WITH MORE TORQUE, YOU CAN SWING A BIGGER PROP. THEY ARE MORE EXPENSIVE HOWEVER BUT WORTH THE MONEY IF YOU WILL BE IN R.C. FOR A WHILE.
THEY ARE ALSO MORE FUEL EFFICIENT THAN 2-STROKES.

2-STROKES ARE CHEAP TO MANUFACTURE, AND ARE MORE SIMPLE IN DESIGN. THEY TURN MUCH HIGHER RPM'S THAN 4-STROKES AND RELY ON TURNING A SMALLER PROP VERY FAST RATHER THAN A LARGER PROP MORE SLOWLY.

HAVING A LARGER PROP ON YOUR PLANE PRODUCES DRAG ON A PLANE IN FLIGHT AT IDLE WHICH CAN HELP SLOW THE PLANE DOWN SOME TOO.

ALOT DEPENDS ON YOUR FLYING STYLE AS TO WHICH CHOICE YOU MAKE. I AM BY NO MEANS AN AUTHORITY ON ANY OF THIS, BUT I THOUGHT I'D PITCH IN ANYWAY. GOOD LUCK!