Little backwards. Alkalines are a last resort for a light like this. NiMH give a much longer runtime at a much more constant level of brightness. They are also far cheaper to run. A typical NiMH AA costs about $2 and will last for around 500 cycles. That's $0.004 per use. That's right, 4/10 of one cent. A typical alkaline is around maybe 30 cents a piece and has maybe 60% of the runtime in high drain electronics.
I don't get one thing, if you carry lots of spare AA alks, why don't you like carrying spare NiMH? You'd actually have to carry less spares with NiMH since they last longer and need replaced far less.
Let's look at a typical runtime graph with some common cell types to show the advantages:
http://www.flashlightreviews.com/reviews/fenix_l0dce.htm