Also, some companies use different oils with different viscosities and other traits in various types of fuels. While other companies have decided that it's not necessary and use basically the same stuff. PowerMaster, for example, has a lot of different lubrication packages (look at www.powermaster.com, they have a great FAQ about this on there). On the other hand, Morgan fuels (who make Omega and Cool Power) now use the same oils and % in both their heli and airplane fuels (I think I read that on their website a little while ago).

For sport flying, fuel is as much a matter of prefernce and seeing what you like than anything.