I think that a lot depends on what you want to accomplish. Are you using these lights to help you find your way, illuminate a tent, or draw the attention of rescuers? Are you interested in protecting your night vision? If I were buying for myself, I'd buy the Extreme 180, because I would want the increased brightness, and I would prefer the directional light of the 180 instead of the omnidirectional light of the 360. As for color, I would choose the green, as I want to protect my night vision as much as possible, and I think I would be able to see better with green light than red.

Doug has some excellent articles on this subject. If you have not read them, I would encourage you to do so. You might take a look at http://www.equipped.org/toc.htm for articles on equipment in general, and http://www.equipped.org/devices27.htm#krill for an article specific to the Krill lights. The latter contains a link to another article pertaining to night vision that you might also find interesting. The URL is http://www.equipped.org/nitevision.htm. I have read other articles about night vision that support what Doug has written here.

Hope this helps.