Dynaudio C4 mk2 or Sony SS-AR2?

I have C4 mk2 for a few years, my bro just moved out of the country, left some toys for me, a pair of Sony SS-AR2 and a pair of Sony NA5ES, he used to play them as a 4-ch system, I just tried them in my 2-ch system, feel like the AR2's sound even more musical than my C4, NA5ES sounded great too, I can't keep them all, just need others opinion, keep C4 or AR2, thanks.