@Sol's comment: I wouldn't rely on linking the CDJs to traktor. i tried it, mapping was a bit dodgy. They do have the ability for HID which would be better, but traktor hasn't updated their software to be capable of that feature (yet). I went straight from a midi controller to CDJ 850s, best thing i ever did. Full size jog wheels are so good, being full size like the pro models. USB support is also very handy. Off the top of my head, main features you gain over 350s: -Full size platter -Bigger screen - can see 3 tracks at once when browsing, as opposed to one on 350s -(Very) Basic Waveform on screen Main feautures missing from 850's that are in 900's and 2000's -tilted screen -full colour display (2000's only) -Slip mode (900 only) -Recordbox LAN Support - which if your planning on using USBs anyway, not too much of an issue -Quantised looping -Different sort options in categories (at least i haven't been able to do it, but you definately can on 900s/2000s) When comparing to 1000s, I've used them at venue, and IMO the 850's are better - main feature you loose is hot cues, but you gain auto loops and recordbox USB support. I'm extremely happy with mine. As with everything though, at the end of the day, comes down to you get what you pay for. If you have any other q's about 850s just hit me or Jaz up and will be able to help you out PS. 850s are available new in black now too