I owned retail workshops for many a year and I know there is always 2 sides of a story. I've had a man try to sue me because he got 2 punctures on the way home after I fixed his car, one car i repaired had a severely mangled accident damaged front mudguard that I accidentally scratched, a little scratch, who then refused to pay for the work until I repaired the whole guard, a long list of great workshop stories like the prostitute that, oh wait, wrong forum for that story. Mate I've seen them all so you'll have to excuse me that your "facts" on an internet page have little meaning to me. Know your audience.
If you had a bad trot then I am genuinely sorry, but Party A and Party B rarely set out to achieve that result. I assure you after 20 odd years of dealing with the public that I was somewhat embittered as well, it works both ways.
... and once again, this is not "Jack's" engine, EPI have apparently done some analysis work for them, the engine would appear to have passed their hands now, maybe the client paid their bill?