There are three Aerotels in the Abu Dhabi airport and two of them are in terminal 3. It is unclear which one is booked and they are a good walk apart, so I was directed from one to the other, then back to the first. The room was a perfectly comfortable pod just big enough for a bed, but quiet and clean. Bed was comfortable and all outlets worked.
I asked for a wake-up at 8:30 to catch a 10:30 flight and was woken up at 7:15. The concierge told me that I needed at least 3 hours to clear US pre-flight customs. We discussed and I ignored him (clearing customs in only 20 minutes much later); but being woken up after 3 hours of sleep was frustrating. There is also NO BATHROOM at this Aerotel. The bathroom is 400-500 feet away amidst a duty free shopping area.
Overall, it was acceptable if I had known where to go and what to expect. Sleeping pods in lounges might be better if you have access to them.