It COMPLETELY depends on your tastes. The Poly gets rave reviews on this site. I doubt I'll ever stay there, though, (using my own money, anyway) because the tropical theme holds NO appeal to us.
The GF feels a bit "ritzy" and "froofy" (as my husband says).
The CR is just that.
I don't think service-wise that any of the three is that much better or different than the other. It comes down to whether you want tropical, froofy or contemporary surroundings on your stay.
One more thought....you can walk to the MK from CR and can walk to TTC from the Poly. That might help in deciding as well.