how about measuring power consumption from the wall? Simply reporting Kill-a-watt numbers at idle, ~10W & full power would work for me. And I don't recall seeing such information from other sources.
If you do use a Killawatt, someone once conducted a good test (maybe at a PC oriented site) that showed it could not measure power with any accuracy until >50W or so. I seem to recall at 10W it was sometimes off by 100%. That having been said, here are the results of some of my own tests with a Killawatt. Note, my published column is from the datasheets--I have not corroborated it with the spreadsheet.