Hi Jose
Yes I have been using the MB4000c for a while. I don't know if yours is an upgraded version but mine looks slightly different from yours. Maybe the MB4000c and teh MB4kc are indeed different mics or maybe the same mic branded a little differently for individual countries?
The point is that for the money the Midnight Blue series of mics are exceptional value and mine certainly outperforms my SM58. (Especially for recording).
Glad you like it.
Best wishes
Tony