I have the (Bomb) Cyclone engine in my MKZ and had the worst case scenario happen shorty after purchase, but all was covered by the warranty and dealership. That said, many report happy motoring on these engines if you just maintain them properly with syn oil and frequent coolant changes. Other than the beyond stupid coolant pump placement, it is a very sturdy and fun engine and Mazda did a fine job tweaking the Duratec....