Native Instruments Traktor S4 MK3

Pros
- Proper layout, all important functions are directly available
- Decent sound card
- Faders, FX and Eq buttons have a decent feel, just enough resistance.
- Easily assignable filter FX
- Filter FX are easier to use / more accessible than channel FX
- Combination of filter FX and channel FX allows for interesting ways to manipulate the sound.
- It's reasonably lightweight, convenient if you want to bring your controller to a gig.

Cons
- Filter knobs have little resistance and feel 'cheap' at first impression. Not what you expect from a device in that price range. But to be fair when mixing it doesn't bother me.
- Personal preference: I don't need jog wheels, I'm fine with nudge buttons. Would have rather had separate controls for every deck.
- Deck switching is prone to confusion, eg. hitting a cue button assuming you're controlling deck C while it's actually A. Practice helps, but mistakes still happen.
- The screens could've been a bit larger and show more info. I got Joe Easton's mod which is a nice improvement, but if Joe can do it, why didn't NI make it such in the first place?

Overall I'm happy with the controller. I can carry it to gigs and it all works like a charm. I might switch if a new version becomes available that replaces the jog wheels with deck controls.

I´m conservative Traktor dj software user for about 20 years.
I had S4mk3. Its not perfect, but i would say - good quality and well build dj controller for money. I had no big issues by using it and it has great functionality, button and mixer lay out.

My only problem was Sound quality. I play 99% lossless audio files and i wasn`t satisfied with audio quality. I mostly play home on my hi-fi. I did 1:1 comparison with my network player and difference in sound quality was hudge.
If i play simple electronic music like 4/4 Techno or house it sounds good enough, but more complex music with lot of live sounds and samples sounded a bit harsh, metallic and muddy. It specially in hi-mid low-hi frequency region with lot of snare sounds and i couldn`t eq it out. I was reading in forums and found more S4mk3 users who noticed the same sound patterns. I don´t know is it because of Traktor audio processing algorithms or controller sound card.

After playng with it arround and trying different kind audio settings i could not get any inprovements so i decided to sell it.

I wish it could have Digital OUT what might solve problem by connecting it to better DAC.

I know, i judge it from kinda "audio purist" perspective so it might not be relevant for most users who play mp3´s on average sound sytems. Than S4mk3 does its job very well!