I appreciate the reply from slipmasterflex but we found another solution that is working out well. It is: Coolmax PS-228 Power Tester - LCD Display, 6&8 pin PCIE
and it has correctly identified good from known bad power supplies we had kicking around (not sure why but that's a different story). I was actually hoping to find a solution that someone else had tried and could recommend. I can recommend this one.