There is a nice review of the JetBEAM JET-1 Pro at
http://light-reviews.com/jetbeam_jet-1_pro/review.html
Looks like the medium output is running on an inefficient circuit, it cuts output by half or so, but uses almost as much power based on runtime.
The low beam is not all that overly hot based on the beamshots.
Tighter beam, dimmer but large spill.
Brightness and runtime go the the Jetbeam, lux reading of the center beam by a lot.
Compare it to the Nightcore on the website above, very neat to be able to look at comparable 1 M beam shots.
I put up the $ for the preorder, and it does not seem such a bad choice. Hope they ship quickly. Saw somewhere they were on Ebay for only $62...
I have the idea that a really nicely made 1 x AA running on Eneloops will be clipped on my belt, with the Fenix L0D CE Q5 (fantastic, tiny thing) in my front pocket.
Not to say the Nightcore is perhaps just as good a choice. Wish either one of them was in stock with a reputable web dealer.
You have to figure they will fill the preorders soon...