My cossie engine was done by Bluesprint and survived some serious abuse, seemed to be very very well made.

Only had one issue, and that was when the oil pressure release valve failed and caused ultra-pressure, bursting the oil filter and fucking the first engines bearings.

But cant see that being a Bluesprint issue as theyd not have touched the pump, just a manufacturing fault.

Id not hesitate about going back there for another engine.