When I first bought the Nite-Ize, it was the so called "white" one and it was dim on fresh set of AAs. That's why I gave it straight away to my dad, now my mom has it. Have not seen the "red" one.
In regards to runtime, I really don't know, but assume that it should be of longer duration. Since you are going to use it for clandestine means, this particular choice should pose no problem given that it's already waaay too dim. . .My opinion says that it is.
Enjoy!