I was in DC for an event at one of the embassies. CitizenM is a very cool place to stay and in a great location. I especially liked the really modern tech vibe with a focus on high functionality and use of space.
I would definitely go back.
There is parking available through the adjacent apartment building, but accessing your vehicle can be mildly inconvenient and pricey if you need to remove your car on multiple occasions.
Overall, I enjoyed my stay and would recommend to friends and colleagues.