Handhelds are a great back-up. I never fly, especially IFR, without a Garmin 195 and handheld radio in the flight bag. Not IFR approved, but who cares about paperwork when everything electrical dies?
Just don't rely on it all the time! I knew one guy who always used one. Very efficient in terms of straight line from one airport to another, but his last night flight hit the side of a mountain.