I really, really like it on a 6 wide Black Knight charge. 6 Black Knight hits with Lances is typically 6 dead models. That's the entire front rank, or the entire flank, meaning no or few strikes back, and you win combat by 1 or 2.
Bad rolls aside, you can make a 6 man knight charge break a Rank and File unit from the side, or sometimes the front. Is that worth 35 points + a unit? I'd think so.