I guess those controllers are really really different. I only had the MC6000 to test and actually did not like it overall in the end. Do not get me wrong the MC6000 is a great unit, however I come from vinyl and those jogs are really small and just did not feel right to me. Also the unit is a bit cramped for my workflow. But if you want to go compact the unit is really great built and has everything you might want.
The NS7 I could only see and touch for 5min, so no real test. However it is built like a tank, but by no means small. This is a huge unit and if you want to go compact, it might not be the best for you. I am actually considering it atm, as I really like the platters and the F/X top bar.
I cannot comment on the VCI-400 as I never saw one in person, looks cool though. I also hope to test the VCI-380 before I make my final decision. I will also hopefully get a Terminal Mix 4 next week to test at our shop (if they release it on time), it is way cheaper than the others (why pay more if it delivers?) but those jogs look really nice, however if there is no option to “itchify” it, it will be a let down and showstopper for me.