I was runing syn m1 5w30 for a while on my original turbo set up and on a 70 deg day at road america i would have almost no oil pressure after 1 30 min session on a mechanical autometer gauge. The engine was in good shape at the time and never burned any oil between changes. I was recently running valvoline syn 10w30 which is what i will be putting in as soon as i get the car up and running again. I will see what type of oil pressure i get with that,if its not good enough i will go with the vr1 race stuff or the rotella. I have spun bearings but it was my fault and not the oils, i didnt know one of the injectors wasnt sealing and was emtying all the pressure from the rail into the engine when you shut the car off. I think there was more gas in the bottom end than oil.LOL
On my maxima vq30de i used to run mobile 1 5w30 and that stuff seemed to work ok, but it seemed to be very thin when i changed it. I am now running regular non synthetic valvoline 5w30 which seems to hold up a bit better, it seems thicker and it looks and feels like there is more in the drain pan after a change, the m1 seemed to thin out to the point of only looking like 3 qts instead of 4.5. I have been running the valvoline now for around 40k. I did try some castrol 5w30 when it was on sale at autozone and with the vq i think that particualr oil is crap, it made noticeably more valve noise at exactly 3k, whereas i was a couple hundred miles over with my last valvoline change. The engine sounded better at 3,700 miles than the castrol at 3k.
I have been running valvoline 10w30 on the g20 for some time now and with over 200k on the clock the car doesnt burn a noticable amount of oil between changes. I dont beat on it that much.
On a side note my friend was using m1 on his evo 8 and switched to redline, and when we installed cams with a friend of ours that runs a shop he said the engine looked like crap on the inside. The car has around 30k on it and he said he has seen some with 130k that looked better. This is one of my friends cars and he keeps it up very well and changes his oil riligiously. The guy that owns the performance shop primarily tunes/ modifies eves and dsms so he has seen his fair share of engines with low and high miles.