Whether you go incandescent or LED get a flashlight that has rechargeable lithium ion batteries. The atomic explosion brightness of some LEDS drain the battery in no time. Of course that is dependent on the lumens of the LED and the size of the battery. I think it's cheaper in the long run to go with rechargeable lithium ion batteries.
I like my LED light in the 5500K (cool) color. It shows a lot of color differentiation and makes them "pop" BUT you also have to be aware of the washout due to the brightness (lumens). I had an old incandescent with the Browning name of it so I don't know who actually made it, it was a more yellow light than I use now. I liked it for blood tracking but the CR123A batteries it took were quite expensive.
If I had to chose I'd go with LED on a middle setting, I don't know the lumens I use but it's not on the retina burning setting. I save that setting for when my personal guide is looking at me.