Him as a out-of-PvMP player I can't say anything yes I see big kin he's leading, nice but that doesn't affect his actual gameplay.
And to that all I can see when I hear Bestone is him hugging Hoarhallow with kin raid. (Believe me that happened and more times than once)
Also to add, his tactics against other leaders arent the best, as they rely on numbers only.
And why take 4 OPs where's the "gain" in that ?
You freeps have to understand, when you take selfishly 4 OPs, no creeps with brain will fight your zergs.