I hit 80% on the head almost everytime, occasional deviations, but usually a standard deviation of <2%.Ha, great quote.
"60% of the time, it works every time"
I brew 4 gallon batches using a 5 gallon round cooler, braided hose, and Barley Crusher set to .032". I consistently achieve between 75 and 80% efficiency. I sparge with 180 degree water. I'm happy with it.