Autox MSP said:synthtic is waste of money on a ecnobox. just change your oil every 3k or 3months you'll save hell alot of money. I've been using 10w30 cheap oil on my mazdaspeed and runs perfect. Friends dad's civic has 200k miles on it and still running strong with dino oil.
I would have to disagree based on the fact that 4 bangers tend to rev higher so it makes sense that better oil would help. That said I had a Sirocco that used dino changed every 7,500 miles and it had 265,000 miles on it when I sold it.
Personally, I use Amsoil and change it every 5-6000 miles with an OEM filter. I bought them at mazdastuff.com for like 5 bucks each.