What clutch did you get for $400??

 

Wow, nissan stepping up to the plate without a huge fight? Good dealer!

And as far as break in. I had my motor replaced due to the same things you are having yours. I have always gone by the method of breaking a motor in how you are going to treat it during its life with you. For me, I drive pretty easy, but I do get on it every now and again, so when i left the dealership with a new motor I got all over it. You do need to change the oil pretty quickly the first couple times cuz of possible metal shavings but other than that I just drove it how I drive it, no babying it. 20,000 miles later on the new motor and it doesnt burn a drop of oil.