GW Water Effects

I'm looking to add some lakes and rivers to my gaming table. Has anyone used GW's Water Effects? Any hints and tips, or alternate product recomendations, would be welcome.

Later

In a recent terrain post on GW's blog they talked about making them with painting the base adeptus battlegrey, drubrush codex grey then water effects.

Important thing to remember is to keep the layers thin, and let them dry before putting the next one on

One thing to keep in mind before using water effects of any variety is the surface you plan to put the effects on. You need to varnish stuff before putting on the effects for two reasons.

1.) Most Water Effects will leech color from the paint underneath them. leading to a cloudy look. If your doing a swamp then it looks awesome, but most people are not.

2.) Varnishing after the effects makes them cloudy.

I would also suggest Woodland Scenics Water Effects. The stuff is stupid simple to use and dries quite fast.