The best way would be to make your own integrating sphere. Aside from that, another fairly general way to compare lights is by doing a ceiling bounce test. What you do is go to a room that has no ambient light and a white ceiling, and preferably white walls (bathrooms are usually good for this). If you already have a luxmeter, then place it on the floor with the detector pointing up. Then place the torch on the floor and turn it on while it's pointing up at the ceiling. Record the number in lux. If you don't have a luxmeter you can still perform this test by using two torches back to back...You'll be eyeballing it, but it's a good quick way to tell which torch is putting out more light, regardless of beam style. Also, if you have a good camera you can take photos of the the ceiling bounce tests, then compare them on your computer screen. Check out Foy's excellent post where he compares a few torches this way.
Hope this helps,
-Match