M90 sounds great, seems like you can’t get away from it too much. Very “accurate” sound in my opinion. M70 is a little too much in the high end IMO, but for some voices it might be ideal. I would be interested to hear the low end with some MV2 on it, I bet that it’s probably incredibly easy to control.
M70 sounds like it has a bit of a mid and treble cut, while the M90 sounds like it has a bump in the high mids along with a bump in the hi's. Now how does the M90 compare to similar price range microphones for broadcasting, like the tried and true SM7B?