Synthetic oil

I switched to synthetic when I started working with a chemical engineer who was a gear head, drove a BMW M3 and changed his oil every 15000 miles. I looked into the price difference, which to me was negligible, and figured if it was good enough for this gear head it was good enough for me. Yeah, I think synthetic is superior. But truthfully a car engine isn't subjected to conditions that would demand synthetic. But, it makes me feel better!