I also got lucky I guess, getting 80-85 and sometimes jumping to 100 on one of them running @ 200mhz.
I am using a server PSU 750w to power all four of my R808's, one is currently at repair so right now it's 3.
I had them at 225Mhz and 250Mhz at one time for a day or so but was scared that they wouldn't get enough cooling, they have never gotten too hot to touch.
At 250Mhz they were nice and warm and with 200Mhz they feel like room temperature, got to get me one of those laser temperature things...lol
I have them in a controlled environment that stays at 65f all day every day.