Convenient but overwhelmed
I had the unfortunate opportunity to stay at the grand hyatt dfw not by choice but by American Airlines cancellation. When the flight was cancelled, we had to stay one more night in Dallas. We chose to stay at the airport grounds due to convenience. The hotel is located in terminal D and is easily accessible by airport tram. 
It turns out we weren't the only people staying due to cancellation. The check in staff reported she was out of king size beds but when we told her we had gold status, she quickly found a room with a king bed. Ironic, isn't it? 
we were hungry and tried out the restaurant and were told there would be an hour wait. It was Easter Sunday and American must have cancelled half of it's flights. The restaurant was poorly understaffed. We sat at the bar and due to our exhaustion, we ordered to go. The bartender was very busy and impatient. I realized why...she was the only person tending to all the customers at the bar, the snack area and the orders that the wait staff was putting in for drinks for the restaurant. Yes, she was the ONLY person. She ran around, flying from one end of the bar to the other, and back again and slamming glasses and wine bottles around. Soon we noticed she was so backed up, the wait staff started pouring their own wine. And not to mention the piles of dirty wine glasses, carafes, plates, sitting on top of the counter. We sat for an hour waiting for our food to go. We were lucky. Apparently people sitting down dining had a 2 hour wait. Maybe it was just a bad day/night. We ran into another couple on the elevator who bought food from the snack bar. They couldn't even get a plastic spoon. That's how bad it was. 
We proceeded to our room. It was right across the elevators. So you can hear everything. The room was very modernized, with a huge window that spanned the entire wall. Everything is electronic, and with a touch of a button, you can control the blinds, the lights , etc. The shower was quite small, the size of one I would expect in city living, such as DC. THere was a tub, opposite of stand up shower, that we didn't use. The bed was firm, too firm. When we woke up at 5 am the next morning, i hit the button "soft light", but it wasn't soft, it turned on all the lights and blinded me, instead. The worse part was hearing people talking and walking throughout the night. The rooms were fine, just request away from elevator. 
We would do it for convenience for traveling, but otherwise I would highly recommend the new omni convention center hotel if staying in Dallas.