I've done a lot of simulations against hyper-agiles, his high speed is usually what decides the matches. I mean, several attacks in a row can make a lot of difference, and with implacable this one hits hyperagiles quite often.
Yes it has only 2 pets and its a big weakness but usually this brute uses COTD like two times in a row very often and also attacks with the good speed.
His big speed also (apparently) makes him use more often stuff like 6th sense, pugnacious and stuff like that. Its quite important too.
I'll do more tests though.