I bought a Nady PA system. One of those 8 channel portable units with wheels and a handle that you can walk around like luggage. It's ok. Nothing to brag about. Serves the purpose if I need an amp when I play out which is very seldom. I break it out every year for a Valentines day banquet, hook my ipad into it and the dancin' begins. The cooling fan in it is LOUD.
Nady= mostly low end stuff that is passable if you don't compare it with too many other things. :)
I'm sure the headphone amp will probably work, but the amps will likely have a lot of audible distortion.