......is that an indication for the condition of a turbo; the free floating bearings for example. Probably a stupid question, but just wondering how easy it should turn; should it be done when cold, or a warmed up engine?

 

I'm not sure, but FWIW my 60-1 hifi with standard bearings spins easily with fingers and my friends GT35R spins freely if you blow over it (and for seconds after) Both turbos seem to be in good shape...

 

It should feel smooth. For a point of reference, if you spin a K26 with your finger tips, you should only get around a turn and a half of coast out of it.
There are probably drastic differences between bearing types.

 

Should turn easily, and not have any "rough" spots or drag spots.

Different bearing types will influence how easily it turns and how long it spins afterward.

 

Are we talking about a journal bearing turbo or ball bearing (or, hell, one of those airfoil bearings)?

Journal bearings only work well once they're up to speed, and they have oil pressure. They depend on that film of oil squeezed between the bearing and the shaft to reduce friction. Ball bearings, on the other hand, always work, because they're self-contained.

So when you have a journal bearing turbo disconnected and "dry", it probably won't spin very well at all, but a ball bearing turbo should spin when you blow on it, like MM951 described.

And if you've somehow got your hands on an airfoil bearing turbo...those things don't need oil, they just need to already be spinning at eleventybillion RPM for the bearings to work