Gary -- many threads on this, very subjective topic. Check out my post, has links to other discussions.
Probably nothing wrong with 5w30. But in South Carolina, there is no reason you need to go that thin, and 10w60 gives the engine better cooling due to the broader viscosity range.
I LIKE OLDER BMWS, PLEASE HELP ME
Fern Green 99 M3
, Conforti Shark Software, Conforti CAI, Dinan Exhaust. Stamped LTWs, 235x40 square, OE Hella heads, ///M
Pedal Kit, Clear Corners, OEM Rear Spoiler, CD43 stereo. MRegistry listing here
Le Mans 2002 M5
, Black/Titanium, Rogue SSK, Dinan exhaust, PSS9 coilovers, Euro rotors, iPod integration. MRegistry listing here