Oil + additive viscosity

Which oil do you use? The 15w50 or the 10w30. Also what kind of oil pressure do you get with each oil? I want to use a thinner oil but I am a bit concerned about dropping too low in pressure especially when you are cruising at about 3000 rpm and the pressure drops to about 48 - 50 psi. Also the noisier ( only sightly noisier) valve train I dont mind it if it doesnt cause problems. Have you or anyone noticed this with different viscocity oils?
Billbo I've been using the 15-50 since switching from Joe Gibbs hot rod oil about 10 k ago , oil pressure hot Idle 35 LBS , 3000rpm 60 LBS .Haven't had any issues and always check dumped oil for any shavings after pouring old oil in container for recycling and magnetic drain plug is clean. I use the new Ryco oil filters (Black type ) as they screen better than your std type but in saying that I use some earth magnets around the oil filter to catch anything just in case. Just being Anal ...