Checking in is a bit laborious but I suspect that's due to Qatari bureaucracy. The staff are great.
The gym is now open 24/7 so I went and shared it with just over other person at 2am. It's good for a hotel gym (10 resistance machines, some free weights, treadmills, towers, elipticals). I think I works have complained, though, if I had paid US$55 to use it without a hotel stay.
The rooms are really comfortable and the people are exceptionally nice. It is, though, very expensive!
If you have Dragon Pass or Priority Pass, you can use the lounge on the lower floor of the hotel rather than paying for room service