They are both 2 quite different beasts. The S4 is designed purely for Traktor and offers very tight integration and Traktor fans really love it.
The Denon is of course also built with Traktor in mind, however integration is not as tight as the S4. However the Denon offers A LOT in a small form factor and has its fans for being hugely reliable (Denon has a good quality reputation) and small form factor. Some say it is a bit too cramped… the Denon is also often used with other software as it does a really good job in VDJ also.
Both controllers have some mileage in them and there are some promising newer controllers also that cater towards Traktor. You may want to read some reviews in our blog to get more information about your choices.
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