I fly with a roger dodger simpit. Love it!
Anyway, I did the keyboard thing too, but the answer to your question is "no". All USB keyboards are equal under Windows, so if you hit an "s" on that keyboard, it's the exact same thing as hitting an "s" with your regular keyboard. Having said that, I've been doing that for years, and haven't noticed any problem. Obviously, need one keyboard to type on, one to be your fake control panel.
Also, while I actually think mine looks really cool, and helps me find things (I did color coding around functional areas), I got bored and built a button box, that, in combination with an old SunCom throttle I upgraded (like Warthog/F15 throttle), gives me all the buttons AH can handle. I used Leo Bodnar's board, which also handles analog inputs by the way, but there is another one that someone recommended to me recently, which, if I were starting over, I might use instead. A bit more pricey though. I'll find the name if you're interested.
