Hi mav, I have just bought and completed the f-16, if you want some photos of my air system installed let me know, I think three airsytems is a bit to much.
I work with full size jets and when you take off you retract the gear and the doors shut when you are on finals for landing the doors open and gear comes down and locked.
How many times do you think you have to go through this sequence on a model, correct ONCE,
on my setup I have only two air tanks, one for brakes and one for doors and gears and you will find you can get about 5 cycles with this setup.
I f you are concerned about air loss get yourself a Tamjets gear failsafe this will activate the gear at a loss of pressure.
If this is your first jet make it as easy as possible, do not go for complicated setups as this will confuse you when the time arises to fix a problem.
Do you have people in your area to help if not give me call.

todd