Just got Aquarian Studio X Coated for my 18" kick, and here is my short review.
First off, they are coated. The more I use coated heads, the more I like them, and they sound really good in all drums. I just like the control the sound has, and it seems to get to the tone/sound I am looking for much quicker, especially on my jazz kit. (Sporting now G1 Coated heads on the toms, and the Studio X coated kick)
As for the sound of the kick, I feel there is much more attack, but it retains a lot off the low end, without much ringing, no need for a pillow anymore. Also when kicked softly there is more definition in each stroke.
Last but not least, coated just looks sexy IMO. And $15 is a drop in the bucket for a good kick head.
Skyler