I just bought Take on helicopters plus the Hind pack for $2.50 US
http://store.steampowered.com/app/65730/
Its still on special until the 11th of March. My impression is the FM is much simpler than DCS choppers but doing the preflight involves doing a walk around of the aircraft so there are aspects that are not in most sims also you can walk around in FPS mode and drive vehicles. There is a patch for Take on helicopters
to work with Arma2/3 so it does improve things in those areas.