Ok, done some research. Anything with the Cree XM-L emitter is rated at 1000 lumens, at 100 lumens per watt. So running its 8.4v 6.4mha power pack it should reach that, but that output would be pushing past the emitters rating. I don't know enough about LEDs to know if that's a bad thing or not. The main advantage of the battery pack will be running time. So I suppose it depends on how much you want to use it.

I've looked around and there are loads of torches running the same emitter with 2 AA's which should get up to decent outputs, they're also half the money of that one above.

Personally I'll be going for one of those with a 2 fish holder. I won't need more than an hours usage at a time anyway.

Matt