I have a pair of the Wisdom M-50 and am planning to upgrade to the M-75 model soon. I cannot attest to the MG 20.1, because I never heard them. Having listened to my Wisdoms for approx. 6 years they are probably one of the most neutral and revealing speakers I have experienced. The active brain (crossover) allows you to custom tune the system to your room. Yes, you can do the acoustical traps rounte but my wife did not want all those "pillows" placed stratigically all around the room, no matter what they did! (And no,she is not unreasonable, I believe she has as much say as I do) I made more sense to me that the system can be tuned to the room rather than the room tunes to the system. Another aspect is do you have children or pets, the M-75 would be more environmental friendly to them as well as easier to clean. If you have a dedicated listening room that you can lock up, disregard the last sentence.
If you do decide to purchase the M-75, Wisdom Audio provides initial setup for new purchases and you can fine tune it to your own listening pleasure.
Choosing speakers is not an easy decision, but it can be fun. Enjoy!