Has anyone used the Saitek X52 joystick and throttle, Saitek Pro Flight rudder pedals, and the Belkin N52TE (or its successor the Razer Nostromo) gaming keypad simultaneously with FSX? If so, did they all work together smoothly or did they interfere with each other? I have the Saitek X52 and the rudder pedals and I am thinking of buying the Razer Nostromo gaming keypad to use it to open various 2-D pop up panels and program some of the keys to use for ATC responses and a few other functions so I wont be stretching my fingers all over the keyboard while trying to fly.

If it is a standard USB device, it will just show up as another controller in FSX and should not interfere with anything else. I have all of my USB devices connected at the same time, which include Saitek yoke, 2 throttles, rudder, X52 hotas, MOMO steering wheel, Logitech G13 (which I use for view switching) -- and they all work fine. The only thing you need to watch for is that FSX has the nasty habit of reassigning axes and buttons when a new controller is connected, so you need to go through ALL of your axis and button setups in FSX and get rid of any that you don't want.

I had used this type of setup, and used each hardware devices profiler to configure the devices. It worked without too much fuss.