My shimano bearings are "cycling specific" and have the same drag. Big fatty bearings have more contact area with more grease to stick to the races. It's less about the viscosity and more about the enormous size of the bearings (relative to normal BB bearings).
Phil bearings feel the same in there, as do ceramics, and you'll never tell a difference when actually pedaling which has been verified through wattage meters.
If you want a "cheap" source of odd ceramic bearings, check out VBX on Ebay.