It will be a little different if you have a spin-on oil filter adaptor -- depends on which filter you use.
20W50 is great unless you're always running in really hot weather, or driving hard. When I lived in Houston, I ran straight 50wt racing oil. Up here in Olympia, WA I run Castrol 20/50. I think I have synthetic blend in there, because that's what was on deep discount. I wouldn't use a straight synthetic, though.