All of the ones with the "w" are Neutral White, as opposed to Cool white. Neutral White is more of a yellowish white color, whereas Cool White is almost a blueish-white tint. I prefer the Neutral White myself.
Geez, I haven't looked at their website in a while, and I can see why you are confused!
They really need a simple comparison tool on their webpage. They do have a comparison link that takes you to a spreadsheet, which you can use to see the differences and so forth. But if you aren't good with Excel I suspect it might be difficult to use.
https://docs.google.com/spreadsheets/d/1WRnPsoYXE9oYKMievC1NOWQyrvSVk8HxkkEMBjAPo_s/edit?hl=en&authkey=CNqP6KIC&pref=2&pli=1#gid=0It is nice to see that their max lumens outputs have continued to increase,as have their runtimes. Zebralight is a good brand- no matter which model you choose you can't go wrong.
Trogman