Re: Less cool the water > the flavor. Ok so...
You'll get bigger/smoother clouds out of colder water, and a stronger taste out of warmer water.
As for myself, I'm with Abu. I usually use half cold tap water and half warm tap water, which leaves the water a bit colder than room. That was it's nice and resfreshing to begin, and as the session draws out, the water warms up, keeping the taste coming.