Me personally, I run ONLY RHP's in my AP t8's and set them on a quality thermostat (Vivarium Electronics is what I use but Herpstats are awesome as well).......then the temperature probe hangs on the COOL end of the cage the furthest distance away from the RHP...this was the advice of Bob at Pro Products as your BP will always have a proper temperature that they can "escape to". I run 65 watt pro-products rhps
I then set the thermostat to 80F....which keeps the hot end right around 92F in a 68-70 degree house.