Nearly every 'chinese' power torque engine (ie after about 1994/95) i come across new or old is scored to some degree have had to through at least half a dozen away (beyond even a hone), and yet nearly ever 'aussie' power torque i come across is in great to perfect condition, go figure! Sure proper maintenance has a bit to do with it, but the older aussie made engines are a much more durable engine. If i ever need a replacement i buy an older aussie made power torque, swap over the later cowlings and ignition coil and she's good to go.
