As soon as I read the title of this post I knew it was going to be "interesting". You can ask 10 different guys what oil they like and get 10 different answers (as you can see). My personal favorite non synthetic is Valvoline (both racing and non racing), what I like about the Racing blend is it has more "cushion" (ash) in it if you run a flat tappet cam. This keeps things happy. After calling ALL the major cam manufactures (a couple years ago) every single one told me NOT to run synthetic oils with their cams (Crower, Crane, Comp, etc...) call for yourself and ask. The reason I got, was because synthetics don't have ash in them. I would love to run synthetics in my flat tappet engine too, anyone have "proof" it is not an issue to do so?
Now with that said, I do run Mobil-1 in my 2000 GMC truck (roller cam). I have run synthetic in the past in non roller engines and didn't see any ill effects. I like the idea of synthetics and believe in them, I am just curious why cam companies don't reccomend them? I am sure it's not so they can sell more cams. I do run synthetic gear lubes and greases.
As far as synthetics go I like Amsoil, Mobil-1. I have heard great things about Royal Purple, but haven't tried it. Red-Line is good stuff too.
Dino oils I like Valvoline or Valvoline, I won't take Pennzoil for free, just a personal thing.