Why I did not like the W...?
... because it did not meet my expectations.
The lobby is a mix of bar, lobby and disco. I arrived in the evening and the music was so loud I could not listen to what the receptionist was saying. Everything is quite trendy and hype ...but really not in such a way you feel welcomed. 
I was given a tiny tiny room. Very trendy but really in order to charge certain prices there should be a minimum Sq feet necessary. 
All is darkish being black and purple the colors I recall best.
Overall this is a trendy hotel with some interesting details but really you as a customer do not feel as the main objective of it all. The main objective seems to be keeping the hype, the "kool" and you should consider yourself very lucky to have a taste of it. 
Not my concept of quality and of a 5 star hotel.