If you are going to spend any time in San Diego, I recommend the Omni Hotel. It is attached to their their baseball stadium, Petco Park (one of the nicest stadiums around), and at the bottom of 5th Avenue, which is the start of Gaslamp district. Walk up and down 5th and over a couple of blocks, and enjoy the restos, the bars, the shops, the people, the scene - very San Diego! If you are going to be at a convention, Omni is steps away from the San Diego Convention Center. A short walk and you are along the harbour boardwalk which is very scenic, and full of buskers, pedicabs …. and I highly recommend The USS Midway, a great aircraft carrier permanently moored along the waterfront.
As for the hotel itself, I found it very clean, very modern, the staff were attentive, service was great, the lobby small but comfortable … just the way I like it!