IMO The RAH looks better than the SS Premium, I can't put a finger on it, but it just looks better to me.
But whatever floats your boat I guess.
Like what was mentioned above the Koto and the GG Bust (I only know of the very first one) are both amazing as well.
If I was to pick, I would rather the RAH...but then again the Cartoon Statue of Fett is amazing as well!
As the Fett Turns...