There was an article somewhere that explains the hot/cold SAE ratings, what the pressure should be approximately and how the viscosity impacts it.
I have been using 10w40 Motul 300V, but I'll try Mobile 1 5w50 for the next oil change (in about 6months/5000kms).
What the conclusion was in that article (correct or not), most oils are too thick when cold, but a lot of them are too thin when hot, ie. 5w30 is not thin/thick enough.

Adi