Whilst I'm impressed by your "c'est la vie" attitude, Will, I can't fathom why you seem to just be taking this on the chin? If it costs you £2k for the motor, it'll still cost you a small fortune in labour to get it fitted by someone who knows what they're doing. If it was OK before it went in to Nationwide, they gave it a clean bill of health and then it went pop a few miles later, my finger would be pointing at them. You need an independent engineer to ascertain what the cause of the failure was - these engines don't go pop on their own. Whatever you decide, good luck with it.