I use the flaps when ever im in a fight and go below 200 and still need to turn, they stablize the AC and keep it from the nasty low level stall that makes so many f6f's auger to there death.
Only using 1 notch doesnt cause much drag, as you would notice if you admistered the flaps and nosed down for a second, very quickly they retract becuase you still have good acceloration and they cannot deploy over 250.
The most common scenerio when i use them is when proforming verticle manuevers, you will find that even with out using any pitch on your stick that it will flip on its own in a nice tight loop, the more you admister the tighter it loops, i would recommend as many notchs that you can get for most average/low speed loops. You can out proform just about any other AC in the veritcal using this method IMO.
Some times i find my self very slow and unstable after a series of flat scrisors (on the deck), here is another instances where they will save you. with 3-full notches you can fly 100 mph and still manuever with out stalling out, although it should be noted with full flaps you will have next to no acceleration.
Hope that helps ya
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