In my mind Sun has better girls overall and mamasan is much nicer. As others have mentioned the mama at luxury seems upset usually. Luxury does have bigger rooms with TS inside them.
I only go to Lux now if I am curious about a girl. I was curious about Emma because of how thin everyone said she was. I am curious about Asa because she is half Japanese so I will probably see her. However, my favorite girls right now are at Sun.