I wouldn't go so far as to claim that air is always as good as non-custom water. My 212 Evo, which is only 6 C hotter than a DH-15 according to a round-up on this site, ran my cpu at 58 C under full load. I upgraded to a Corsair H90 aio, and I'm seeing temps of 43-45 C under full load once I figured out to run it as an intake instead of exhaust. For me, I'll never go back to Air, or even Big Air like the DH-15.