Stayed there about 2 years ago for a while ( few weeks).
It a nice Hilton, quite old in appearence and setup but if it's been renovated it should be better.
It has a great sports club inside with raquetball courts and a very nice gym.
There is no exec level or lounge. Breakfast is quite good. There are a few suites with large balconies that are pretty nice and are the most you will get as a diamond.
As far as location - it is pretty far from anything but has a metro train station within walking distance (train runs every 2 hours or so) and an Amtrak station within 2 miles.