Staying in an Executive / Deluxe King right now and having a very mediocre stay.
No Diamond line upon check in. There also no organized line, so agents were just pulling people at random. I handed over my ID and credit card. Got nothing more than a Hello and then a Thank You with my keys. There was no explanation or recognition of my Diamond benefits and no offer of late checkout.
Room is fine; average Hyatt Regency. Note that this hotel has fairly thin walls, so I was able to hear people in other rooms and even when they went to the bathroom. There was some trash left over from the previous guest also. Blackout curtains allow a fair amount of light bleed in the mornings, so don't expect them to work fully.
So, the hotel is great for mattress running and/or just for a quick trip to DC. I wouldn't recommend it for anything else.