I'm in no way associated with Advance, but they have a great oil deal that ends tomorrow for folks who change their own oil -- both on Mobil 1 & especially Pennzoil Platinum Full Synthetic Oil. I bought two 5.1 quart jugs Pennzoil Platinum (10 qts), received 2 K&N filters, and after $20 total rebate will cost $43 vs $140 oil change at my usual place & still have an extra filter left over. My usual shop sometimes has used Mobil 1, sometimes Pennzoil Platinum. The Boxster gets the oil changed every year and I only put on 5k max per year, so I think no matter the brand preference, this is the best way to go & thought maybe others would want to know about the deal. Here's the link if you want to look at the circular...
http://shop.advanceautoparts.com/wcsstore/CVWEB/Attachment/staticbusinesscontent/image/sep-2012-flexi.pdf