I'm not sure that butchers are that aweful. 5 with double claws, 31 attacks on the charge, 26 if disordered, rerols failed hits and wounds. Rending on 6s.
Hits on 3s mostly
27.5 ish hits,
20 wounds, 6-7 at ap2. Will knock 2-3 cataphractii, at initiative.
Say they get to swing back at i1 with fists. 6 attacks, hitting on 3, 4 hits, wounding on 3's due to the -1 str.
3 wounds. 1.5 guys die on the swing back.
They really shine against large blobs and veterans. And if you send in a beserker preator with paragon and the -2 ld, they'll do work. But they need a delivery system.