Is OS X 10.10.2 faster than Windows 8.1 on same hardware?
I personally feel that speed tests such as these are of theoretical interest but not of any value in the real world.  After years of faffing around with windows and comparing to Mac after I saw the light, speed issues become a moot point:

Work flow windows: switch on-> wait 20 minutes for latest update to install->spend a further 20 minutes repairing the issues the update created->have a cup of tea to unwind->back to windows and with any luck the thing would work (about an hour total + time to complete initial intended task)

:Mac OSX workflow: click mouse to fire up (1 second)->open app ->  good to go (about 4 seconds+time to complete intended task)

In light of this, who cares if 1 machine takes 1 or 2 more miiliseconds to "theoretically" complete a given set of CPU calculations?