Switching from Conventional to Mobil 1 - Please help?

I was first introduced to synthetic oil as a military flight line mechanic. There was a component on the aircraft I worked on that used it. This thing spun at unbelievable RPMs and under alot of heat. Whenever this component needed servicing, the oil in it was never replaced! Only cleaned/filtered. From this I made the mental leap to use synthetic oil in my car. In a 4 year period I put 200K miles on my Nissan pickup using Mobile 1. Never changed it, just strained and reused it! When I had to replace a head gasket after it sprang a water leak (normal high mileage wear) there was no ridge at the top of the cylinder walls! Still worried about wasting money?