A little devil's attorney here:
I can mine 1 MNR, and in same amount of time i can mine 6 HVC (just tested it).
Given the best buy @ HVC whis is 775s, in order to MNR to be profitable, (compared to HVC) it's price should be 4650s.
Current best buy is 2000s ...
will go up when the reward will be at 50, some people are just giving at the moment the "easy to get" MNRs