Reply to XONE 4D vs XONE DB2 or DB4 vs Pioneer DDJ-SX for sound quality + use with traktor?

Hello All, I have been playing with my traktor S4 for about 2 years. I am an audiophile and home dj with very good speakers. I discovered my S4 sounds better when I use external mixing through my DATEQ Apollo mixer, but then it is way more difficult to use of course.
I was believeing about a XONE 4D because it has an analogue mixer and is supposed to work good with four decks traktor, but the in the music shop they said it was outdated and a Pioneer DDJ-SX mapped top traktor or XONE DB2 (+ extra midi controllers like DENON SC 2000) would sound better... Would a XONE DB4 sound even better, or has it just more options?

Now I am confused...
I want the best possible audio quality and easy use with four channels of traktor pro...

Has anybody compared above units sonically on the same (good) soundsytem?