Just to clarify on my use, I don't use Double Thins exclusively. In fact, my tom head of choice is the Classic Clear (single ply). I use the Texture Coated heads on my snare drums, and occasionally on my toms.
I like a big, open sound with lot's of attack. The Double Thin is the closest thing I've found to a single ply head, even though it's a two ply. The reason being that the two plies are very thin, so the head doesn't roll off as much of the high-end frequencies as other two ply heads. This also allows for more attack (crack) from the drum, like what you can get from a single ply drumhead.
Aquarian uses a Vacuum Processâ„¢ which eliminates air bubbles and wrinkles between the two plies. This allows the plies to move together as though it's one ply.
If you are a heavy hitter, and really dig into your drums, the Double Thins may not be for you. They will dent up simply because the plies are thin. If you plan to use a two ply drumhead for sole purpose of lasting longer through heavy playing ... this head is not for you.
I'm not an "avid" user of the Coated Double Thins ... and for me, they rolled off too much of the sound I like. If you think you want more of a rounded tone, and something that will take the heavier playing, getting the Coated over the Clear versions of the Double Thin would probably be best.
You can find out more by reading the descriptions on the Aquarian website:
www.aquariandrumheads.com