I believe in babying mine. It is my understanding that it is not how fast you have driven but how many times the engine has turned over. Take a police car for example, they leave them running outside the donut shop even. The car may not have but 100,000 miles on it but the engine is worn out because of the amount of times the engine has turned over. I never let mine get above 2,000 rpm when it is cold and only rarely floor it. It does feel good when it comes on the cam though doesn't it.
There is nothing in the world like strong inline six.