There are more people here besides me, really. Synthetic is by far the best choice for all three compartments. The main choice is Amsoil and Mobil one motorcycle oil. No slippage or extra leakage. Glad your digging the UC.
Synthetic all round. In both the shovelhead and the Suzuki I'm currently running Castrol RS 10W60 auto oil, and it works fine, but I'll be switching to an oil that's easier to find locally. Prolly Mobil or the local oil company Aral. Don't know what their oil really is, they badge something.
One thing that has come up recently on another forum is using a heavy duty diesel oil all around. I used to do this on cars because of the greater detergent content keeping everything cleaner. Don't know how well it worked, but it certainly didn't show anything bad.