Went to see the sights in DC with my family (wife & 2 small kids) plus my father. We got a 2-room suite: me & wife in one room, dad in another, kids on the pull-out couch. It was a huge savings compared to purchasing two separate rooms.
The hotel was what you'd expect from a Residence Inn: clean and well run. I'm sure there are fancier places, but for the price it is a great deal for business or family travel. This hotel was close to the Metro station (you could walk or the shuttle will drop you off / pick you up). The free breakfast buffet was great. The free drinks and snacks at happy hour couldn't be beat.
All in all I highly recommend it.
Tip #1: If you stay there to see the sights in DC you don't need to rent a car. The hotel will take you to and from the airport. They will take you to and from the Metro station.
Tip #2: Put their phone number in your cell phone. That way you can call for a pickup when you land at the airport. Also you can call for a pickup at the Metro station if you don't want to walk back to the hotel.