I stayed there earlier this month and had a great stay. I had a beautiful suite on a high floor with a great view. All of the staff that I had contact with were extremely pleasant. In fact the person at check-in was very welcoming to me as a Platinum.

At this point I am planning on going back this week, although I might consider the Reston if I hear more positive feedback.

My only problem with Tyson's Corner is that it is far from the Metro ($12 Taxi ride), although there is limited shuttle service. It is also a bit of a distance from the mall ($6 taxi), also with limited shuttle service.