The Surefire L6 is a very nice light that is bright and powerful. But I would rather you get an incandescent if your intention is to spot animals about 300 feet or more away. To me, LED lacks the full spectrum to really bring out details compared to an incandescent light. LED lights are way overpriced too. You would get better lumens per watt and dollar if you go for an incandescent.
I have been visiting a rural and rustic island somewhere in Singapore and one of our past times at night is to spot animals like wild boars and owls. I used LEDs for general illumination like walking and cycling. The L5 I have with me is very bright but I find it quite hard to make out details as fast and well as my M2 on P61 lamp and M3 on MN11 lamp. With my L5, everything just looks monotonous but my incandescent brought out all the details.
You may want a small LED light for general use and a powerful incandescent for long range lighting needs.
Recently, I had some chance to play with my friend's Pelican M6 and I am very much pleased to see it's power for long range usage. Although not as bright as my M2 and M3 on high output lamps but the design of the reflector throws the light really far. To me, that is a good light for spotting animals. If you have more budget to spend, go for the Surefire M3T which is a lot brighter.