Its been a month since I got a new program called, Mixed in Key and I have mixed feelings. To sum it up, Mixed in Key identifies the key, BPM, and its energy (part of the latest release) of a song. This is supposed to help me know which songs will mix with one another.
It does what it is supposed to do, and it does help me find two songs that would work in harmony together; however, I often find myself mixing to the harmony rather than what song the crowd would want to hear next.
Mixed in Key also has this "energy" metric that takes into account build ups in songs and associates those build ups with a numerical number 1-10, 10 being highest energy I don't know how I feel about this yet, since I can see me falling into a trap where I base my next song on a number the program made.
I think it is a dangerous tool that a beginner could use to fall into a robotic way of DJing. You would assume that if it blends well, then it mixes well. You have to be careful that even though the songs work together nothing works better than experience and your own ear.
That being said, for $50 dollars it is a great investment and I would recommend it to any level DJ. The main point to take away is that this software helps. It does not do, it assists.