answers to your questions...
Yes, Mobil 1 is a great oil, but only for gasoline engines. The one you need for diesels is Mobil Delvac 1-- a very expensive, quality oil.
BTW-- the only real oil requirement for our engines is the CH-4 rating.
Whether it is worth the money is your decision. There are many people on here that feel strongly both ways. What it really boils down to is whether or not you have and are willing to spend the money.
It's not whether synoil is better or not; it's CLEARLY a superior oil, as far as lubrication and such goes. The debate is whether or not it is cost effective. Some claim it is, some claim it isn't. There are instances of each.
For me, I want the very best oil I can get my hands on, and I don't care what it costs IF i have the money for it.
It's what IN the bottle, not on the label that counts. .
HOHN