Here is a previous thread on the matter:
http://tentenths.com/forum/showthrea...&highlight=oil
Everyone does have their own preferences as ACE M says. If we are talking road car based I agree with what he says (I know little of brand new racing engines). In the other thread you see people who use really thick stuff in older engines.
We have just changed engines this year from 6 cylinder to 12 and our starting point is Magnitec. It takes a lot of the stuff too, but for an extra few pounds I felt it was worth it.