The new 800 has a 96kHz/24 bit A/D converter which no other mixer on the market today has.

I've got an 800 that will be comin my way.
I got a chance to play on one (know a buddy who works for Pioneer) and all i have to say is

This thing is un freakin believable! I was literally gettin ready to pick up an Xone92 but as soon as I tried the 800, those plans were done with.

Pioneer has basically taken sound quality to the next level.

I promise I'm not a pioneer sales guy either!

I am definately one who can't stand seeing someone over use effects but I will say this, the effects on this thing are nutso! You have so much control over each effect. And as dumb as it sounds, sometimes if the DJ booth is dark and you can't read which effect you have selected (like on the 500 or 600), this one reads out which effect you selected on its digital display.

The midi funtions are really cool too. As the mixer was hooked up to Ableton Live, you basically have the ability to turn your 800 into a controller like Sasha's Maven.

And lastly, for those who like to mix harmonically, the Auto Harmonic Tuning is a dream come true! I only touched the tip of the iceberg with it and like they say, the tuning does you no good if you don't know what keys go together but if you do (i knew studying that would payoff, lol) it can really make a mix sound tight.

Bottom line, play with it for yourself, its expensive, but in my eyes, well worth it!