I should have emphasized some points on instrumentation in a flight sim. Display only (e.g. no input from the user) is fine when you just want to read it (radar alt, airspeed, attitude/adi, etc). However, maps, radios, or multifunction displays require you to touch/mouse the bezel buttons, knobs, etc. This applies to both commercial or military. You can alleviate this by having controls on the grips, but there will be things that are not typically reachable from the cyclic or throttle/collective in the real aircraft. So, you can bend the realism and put in there so that you can change it while your helmet is on - or just ignore it. That's why the helmet is more of a niche device and not typically used for training - but would be ok for gaming.