Have stayed twice for the weekend for a quick getaway. We live in Los Angeles. Have stayed at several of the other hotels in the area, the Solamar and Hilton being the best of them.
First, the negatives: $30 per day valet fee (ouch). They do warn you though and there is a lot between the hotel and the ballpark which is a lot cheaper. Can be noisy in the halls at night. Quite a few private parties with beautiful young and drunk people in some of the rooms. Rooms were clean but housekeeping was erratic. Still not sure if there was an actual turndown service. Phantom extra charges for reasons that weren't clear. I was afraid to even breathe around the mini-bar. And if you like uncomfortable modern furniture, you'll love this place. Wear ankle pads...trust me.
The positives: THE best location. Great bars. Nobu right in the hotel. A buzz in the lobby and all around and within the hotel that lets you know this is the epicenter of the Gaslamp quarter. You will smile when you walk in. Super-friendly , young, attractive, and energetic staff. Exciting place to stay.
The bottom line: The hotel offers an experience. If you feel like doing "trendy", this is your best bet. The Solamar is more refined with a somewhat more mature clientele. But it is also slightly less "hip". The "W" has a mediocre location for a short stay. If you want the great location without the pizazz, try the Hilton. Otherwise, the Hard Rock is a fun alternative.
Gratuitous tips: book Nobu BEFORE you arrive. Lots of great steak houses. Donovan's is the best, the Palm the worst. There is a new Zagets guide for San Diego. Stay the heck on our side of the border. Check out the bleachers at PetCo field if their isn't a game. It's a park open to the public. Carry a little pop-up map. Have a Mojito at lunch; you will ahve a better time.