While I still prefer my KFL's, the Aqua is a close second. I really haven't had any trouble building it, no wobbly tank, no leaks, no dry hits, etc.
I find the vape is warmer and more dense on the Aqua, but a tad more flavorful on my Kayfuns using the same juice. My out-and-about is currently the Aqua in hybrid mode on the Origin due to its small size.
The Aqua also has to be filled A LOT more due to its smaller capacity and the dual coils guzzling juice.