Hennesey's reputation goes beyond a few broken cars - every car enthusiast that frequented message boards many years ago also remembers his piss-poor forum attitude to customers and general disdain for anyone that complained about not getting their car back. Were these customers justifiably upset? Who knows, but the reaction from Hennesey was far worse.
I think its less of a choice about whether he can actually build a reliable car and more about whether he's even trustworthy and/or offers good service. Evidence points to no.