I bought the NX plug-in when it first came out, thinking it was a pretty neat solution to mixing on headphones. While it does give you a different perspective than just using headphones alone, it's not quite what I was expecting. I don't mix in surround, so the surround mode made little difference to me. I ran some stereo mixes I'd done through the plug-in and wasn't sure what to make of it. Also, I turned off the head tracking, as that was more of a "look at that!" selling point than anything else. I'm always in the sweet spot. Anyway, the EQ changes when turning the plug-in on and off. The stereo image changes too, unexpectedly, but I'm not sure the change in EQ is a good thing. I'd be willing to bet more than half of listeners today are using ear buds or Beats headphones. That got me thinking that maybe using the NX isn't such a good idea for mixing a song with headphone playback in mind. The listener certainly won't have NX to use to hear what I hear. So, in my opinion, NX is a nice idea that just leaves something to be desired.