When I was doing research into protein powders I wanted to avoid whey. But with rice protein I was concerned about possible arsenic contamination (as Peak mentions on his page). I found http://growingnaturals.com/. They claim to test their rice protein for heavy metal contamination. Maybe other suppliers do this now too.
I've tried their rice and pea protein powders and really like both.
Jeez! Man, I learn so much doing this forum. Much appreciated Osprey. Will check this out later.