My son did it when we were there over the 4th. He absolutely loved it!! and we loved watching him.
Only thing is ...make sure you block out enough time.
They told us to be at guest relations outside epcot at 530. We walked out of living seas at 800. the dive is 45 min or so, but the orientation, and the after dive time is quite long. We missed our dinner...but that was because we didn't clarify what time he would truly be finished.
We bought the dvd of course, and really enjoy it, although it is short.
If you take pix outside the tank looking towards the glass, take it at an angle so the flash doesn't bounce back. if you have to use a flash. My pix turned out so much better than I thought, I only took 3, because people told me that wouldn't come out because of the flash. They were terrific!!
Also, try to stay in 1 spot, the underwater photographer filming the dvd tries to include your diver next to the glass with you! We kept missing him, but others stayed in 1 place and are in the dvd.
It really is a great experience for everyone!!