Although I didn't get the chance to try the pool, the fitness center was nice. As for the location, it was great for what we wanted to do--walking distance to Pike Place Market, the monorail to the Space Needle, Pioneer Square, and Safeco Field (although I wouldn't recommend the walk back from Pioneer Square or Safeco Field simply because it is mostly up very steep hills). I would certainly recommend this hotel to pretty much anyone looking for a great stay in Seattle!
As a side note, this was also one of the stops on the shuttle bus from the airport, which was about $12 per person when I was there. We had to take a cab to the airport on our return because our flight was so early; this ran us about $40.