Let me ask the question a different way (and I may be misunderstanding Gabe's reply (the one he's linked).

It seems that by using the chiller certain testing peculiarities are introduced that would make the use of a "normal" pump inappropriate in some way (correct Gabe?). If that is the case, and the use of the chiller is to eliminate the variable of room temperature (another assumption on my part) then if we assume the room temperature is very constant (maybe not) wouldn't the use of a radiator eliminate that and allow the use of a readily available pump?

I guess what I'm getting at is the good old real world test scenario. All roads seem to lead back to the beginning

But let me say this. I'm not saying Gabe's tests don't have merit (and yes I am very aware of what the scientific method is and variables) but... I just can't seem to get it out of my mind that the lab you use Gabe seems to introduce it's own set of variables that might not be representative. Maybe I'm completely off base, and I can't quantify them well, it's just a feeling (and yeah feelings aren't very scientific )