I'm running a 6.0 cooler and saw big difference in the temp after adding it. For the longest time I couldn't get it over 120* now with it being 100* everyday I see 170* on the gauge once in a while.
They are not all identical. The 03-early 05 are larger than the late 05-07. The later ones are more efficient, so the result is the same with any 6.0L cooler.