If I have to rank top Mws of all time, I have No choice but to rank Anderson #1 based on his UFC title defenses alone. However, it's my opinion that the well rounded and iron chinned (still, unbelievably) Mousasi that we see today could/ would get prime Anderson to ground and win.... just my opinion. Anderson looked very human vs guys like Maia and Leites.....just to name a few ( and look what Gegard did to a better version of leites). Again , just an opinion and if people were to ask me if I can see one fight (and I admit I have a bias towards mousasi), Today's Mousasi vs . Prime Anderson would absolutely be one of them.