I already know there are other threads with this.
Driving the cars is pretty bad.
Flying helicopters is a little better, but when it comes to accuracy, its worse than cars.
Ask your developers to take off, fly to a random location, and land without crashing or damaging yourself or the vehicle. If they can't do that simple task 10/10... than its wrong. Sorry, but I believe that.
Suggestions.
Turn the responsiveness down a little bit. Needing to pull the helicopter out of a dive by sliding my mouse off of the table is excessive. Trying to land will in hover mode is fail. I need to move 10 feet forward... the heli dives bombs into the ground. Hover mode, landing, the helicopter strafes left or right... 1 foot above the ground it flips sideways.
It's too much guys. Tone down the sensitivity. while in motion, the helicopter needs to be smooth. I have flown helicopters. It's half as hard as you make it, with less controls.
Driving Vehicles.
I drive cars and trucks. I driven trucks, used double cluthes. Your vehicles drive, again, way to sensitive. It shouldnt be a battle to keep the vehicle in a straight line. Take away all the buttons. Think Halo. Sorry, but driving vehciles in so many games is so off the mark. Halo, easy... fun... not difficult... I would rather drive a a 65 Cadillac on a dirt road @ 100 mph than your ATV's.
The controls are excessive. The buttons, excessive. The turning, Excessive. Easy it off, slow it down, make it more fluid.