My wife and I spent the week of 19th - 26th April 2013 diving with Emperor Divers. We had three days on the Concorde Moreen Beech Resort House Reef and 3 days of boat diving out of Port Ghalib.
Some of the dive sites are a little beat, but that is the fault of us divers. Especially you underwater photographers that kick and grab everything so that you can bring home the perfect shot. Many divers I have met do not realize the destruction that they impose when they unknowingly molest the coral, specifically the Zooxanthellae - google it before your next dive/snorkel trip) . That was my save the coral reefs rant.
Many of the dive sites were very healthy, beautiful, and and it will stay that way if everyone uses better buoyancy control.
In regards to Emperor Divers, I was very impressed with their attention to safety. They gave thorough boat and emergency action plan briefings as well as comprehensive dive-site briefings. My wife and I are both Padi Instructors and we recommend Emperor Divers, especially if you have a rating below Rescue Diver.