Howdy and welcome to the forum. Good to have another sound and light guy on board 🙂
If you are referring to harmonic key detection, then be assured that MIK will do this MUCH better than VDJ, according to a recent test by our friends over at DJ Tech Tools.
So yes, you need to pay something, but you get a lot of extra. Not just the quality of the key detection, but also stuff like energy level detection (which is by no means a forcing parameter, but I definitely like having it, especially having a typical mobile DJs ridiculous collection 😀
Greetinx.
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