On the glo-toob website they say white is brightest and easiest to see; this is borne out in my experience as well.
jamesmtl514, so sad to hear you do not like your Glo-Toob! Lots of us love our Glo-Toobs around here...
I'm a big fan of the Glo-Toobs and I will say that the lithium tubes are pretty bright! I can totally use them to navigate around the house at night. My guess is that in terms of "throw" (which is the antithesis of this beacon designed to be seen), it is like a bright cell phone screen in the dark--there's not much of it. Yet, it feels like navigating with something like a 4 lumen light which is enough in pitch black--more than enough, actually.
In holding them, the lithium light is pretty big and somewhat cumbersome compared to the standard. I think that I could get used to the standard and it could really be a super-last-resort emergency backup light. The Li could be a decent tent light and could probably be used for walking along a dark path if all else failed. For getting around the house at night, they are both more than enough and are really fun since they don't really throw a beam anywhere, but are more like lanterns.