Its all about details and the staff
Had a nice stay in the W San diego. The staff was very helpful, they gave us a lot of recomendations. The lobby its small, but have a great eclectic decoration with a bar, and on saturday night,there was a dj. The front desk had complimentary little green apples in the deck.
We stayed in the room 616,overlooking the back parking and some office buildings. The room was a little more spacious than the average american room, with cool stuffs like the kaleidoscope, the ipod deck with great sound and the window seat. Loved the bliss bathroom products.
The location was nice too. It was in the middle of the gaslamp quarter and little italy.There is a seven store 2 blocks away, although I do not recommend walking at night, unless you are heading directly to Broadway street. 
It was a shame that the rooftop was closed when we went,but we received a note from the manager offering free transportation and entry to the pool of The Westin hotel.