Superb location - 5 min walk to downtown or central Capitol hill but tucked away in a quiet street next to Freeway Park. Also close to bus routes and Convention place bus terminal - you rarely need a car for getting anywhere in the city. If you want to explore further afield you can be on the freeway or at the ferry terminals in a few minutes.
The apartment is spacious, clean and tastefully decorated - it struck a nice balance being warmer and more intimate than a typical hotel room but without the feeling that you were staying in someone's home. Overall well equipped (including good quality kitchen utensils, etc.) - Andre and Joel had obviously paid a lot of attention to practical details and we never really found that the place lacked anything.
The hosts keep out of your way - we never met them face-to-face - but were very friendly and extremely responsive to any of the questions we had.
If you want a great base to explore Seattle you couldn't ask for better place to stay.