I bought a used NuForce STA200. I probably have less than forty hours on the JBL's. My impression so far is they're a fairly decent match. Of course, as I mentioned already, my experience with speaker systems is very limited. The only comparison I can make is with AudioEngine A5+ active speakers, which have a pleasant, unfatiguing sound, but the JBL's are more resolving and have much, much nicer bass.
My only complaint is, the higher frequencies could use some taming at times when listening to certain rock albums.. I'm also running my setup out of a desktop pc for the time being, which I know isn't ideal.
Edit: Sounding better after switching from Foobar to HQPlayer.