I 100% agree, I think Tin did a test of the UD7 Vs M4E remember that? He used his IR camera and took shots. Pretty interesting stuff.

of course then you get into the mess of which board has higher switching frequency, which board has a more aggressive PWM scheme, and which board has more phases, which infact would affect the temperature.

Of course it is interesting to put up too boards and compare none the less. I do however agree that IR camera is the best way to do it. Of course if most reviewers don't have a scope how can you expect them to have an IR camera of any value? The FLIR ones are like $1000.