I've been using Traktor 3 for some time and wanted a midi controller to get away from only mouse control. A DJ friend highly recommended Vestax kit so looked at the VCI-100 to check spec. It had all the controls I needed for my bedroom dj style, so I bought one.
The unit is very well built and feels a quality item, which is just as well given the price. It's just the right size too with well laid out controls for easy access while mixing and each knob, button etc has a solid touch and is a pleasure to use. I don't scratch myself but the 'jog' wheels bowled me over as to how much they make you feel you're controlling a vinyl deck. I use them for track searching, pitch tweaking and deck braking.
A ready made midi map is downloadable from the Vestax website which you import through Traktor in a matter of minutes. I've found all the controls are mapped just fine in the way I want them and have had no need to change anything. The VCI-100 has no problem being powered and driven from a USB port on my computer which is so convenient.
I can't recommend this midi controller enough and I'm amazed at how in control I am now of Traktor - on the fly looping, effects and EQ are a breeze with VCI-100, you'll never need to touch the mouse again!