My M103 car is around 267k from what I can recall last time I drove it. Going to do the head summer '10 hopefully. I have three A/C systems to finish first.
I do have some slower starting when totally cold... i.e. excessive cranking.
And I do foul out two plugs (number three and six) every three to five months along with oil consumption and leakage of around one quart every 700-1000 miles. Of course the oil/plugs depends on how much I drive the vehicle.
When the trans dies I do believe I will be converting the car to a five speed.