I have demoed both of these racquets.

Wilson [K] Factor is like no racquet i have ever hit with before. Its kind of hard to describe, but the spin and control are very eclectic, its like nothing you have ever used before. It hits with average power. Heres an analogy:

The Wilson [K] Factor is like a whip.

The Babolat Aeropro drive offers tremendous power and a quick swing. However, back to the analogy, the Aeropro drive reminds me of a sledgehammer. If you get a good backswing and you are prepared for a ball, you can deal some tremendous power and speed on the ball. But its not very good with volleys, where there is no swing and you have to maneuver the racquet quickly.

In summary:
Wilson K Factor swings like a whip.
Babolat Aeropro Drive swings like a sledge hammer.