My husband and I stayed here for one night, in between our flight back to the U.S. from Europe and our flight home. We chose it because we are Hilton Honors members, and they offered a free airport shuttle.
On the plus side, the hotel was very clean, our room was nice, bed was comfortable, room service was remarkable delicious, and they offer shuttle service anywhere within a mile or so of the hotel so they offered to take us to the nearby mall if we wanted (though we didn't take them up on this offer).
Our 8 hour flight arrived at Dulles on time, and we got through customs in about 30 minutes. We were looking forward to taking the shuttle to the hotel, quickly checking in, and resting--we were both exhausted! Unfortunately, we found that this hotel prioritizes flight crews over ordinary guests, and we had to wait for 30 minutes in parked shuttle at the airport for 2 full flight crews to arrive. Once at the hotel, the flight crews all got their room assignments and rooms keys first--even though we were the first people on the shuttle! They did offer us extra cookies, and some courtesy "honors points", but next time we'll likely pick another property that doesn't show such a huge differentiation between non-airline guests and flight crews.
Last thing to note--this may be the case with all airports near Dulles, I can't say--but this hotel feels far from the airport to be an 'airport' hotel. Definitely over 5 miles away--which may not seem like much, but If your shuttle hits rush hour on the freeway in between the hotel and the airport, it can take awhile to get there.