depends on what you are flying. i put a 4 stroke in a plane that likes some speed (yak 54), it just didnt work well, put a magnum 52 2 stroke in and boy did the yak come alive.
as for the torque argument, with a 13x4 on a os ax55 it will torque roll my plane faster than i have seen anything ever torque roll. (mojo.40)
yes the throttle response is better with a 4 stroke, and they sound cool. however they cost a lot, and dont save you any money in the fuel area. (most 4 strokes like 15%+ nitro, you can run a 2 stroke on 5% which is much cheaper than 15% and will last longer)

3d, 4 stroke is best, 2 stroke will work fine
pattern, either or
sports flyer, 2 are best, 4 will work fine
speed planes, 2 stroke
big, heavy planes that lumber aroung, 4 bangers.
thats my opinion