10,000 miles is too long on oil change if your planning on keeping your car for a 100,000 miles. Going by the Maintance Minder?Mobil 1 Extended Performance Oil claims you can go 15k miles between oil changes. I go no more than 10k using the Mobil 1 Extended Performance filter with it. If your changing your oil more often than that, then you can use a less expensive oil. I don't think I'd push the Kirkland Full Synthetic more than 5-6k miles. Going 5-6k you can use a lower priced filter and save more.