I have owned both the Krill and the Glo-Toob. After getting my Glo-Toob, the Krill went away. It is a P.O.S. by comparrison. The Glo is brighter, stronger, completely waterproof, hands down an excellent bit of kit. Although the Glo-Toob uses an N cell, they are cheap and easy to find (here in the U.S. at least). The batteries I purchased are Lithium, so have a long shelf life and in the unit last upto 80 hours of runtime on the FX, 30 on the regular model. You won't get that performance from the Krill. IMHO, you just can't go wrong with the Glo-Toob.

I currently have one Red "Regular" Glo-Toob I keep on my Maxpedition FatBoy pack, and a White FX model on my B.O.B. The FX is surprisingly easy to change settings on. Also, if you check e-Bay you can often find the Glo-Toobs for much less than the web-site prices.