guess i'll pipe in my 2 cents on the whole oil thing....
yes you can drive farther (more miles) on synthetic oil as it will change viscosity for a long time (unlike crude). with that being said think about what you are doing to your engine running 25000 miles (someone claimed that above with amsoil), you are not changing your oil just because of the viscosity break down, but also because it gets dirty as hell...we did a study on this at the vocational school i went to...while the oil companies are right that synthetic will easily last 7500miles that means you are running all that dirt and carbon around in your engine that much longer....to do so is the most riduculous thing in the world....if you can afford to drop money into your car you can afford to do oil changes,it is better to run crude and change every 3k than run synthetic and change every 7K+

as far as not needing to prime (fill before installation)your oil filter good luck the oil comes from the filter before going to your engine, so essentially you are dry starting your engine damming you bearings...just fyi 3mins without oil = 100,000mi on your engine so every time you start you car without that extra 1/2qt that goes in the oil filter you are putting on roughly 10K extra miles on your bearings.....good luck!!!!!!

-Mike