I think it varies from light to light.
I'd say mine is cool, maybe leaning toward blue.
I have a few Q3-5A's in the mail and may have to swap the emitter after seeing what it did to my EX10. The color rendering is like nothing I have seen from an LED...Awesome!
It's not just Surefire. It's almost every flashlight company that makes LED light.It's evidently a crapshoot with Surefire.
I was under the impression that some companies "sort" by tint bin more precisely than others. Some even go as far as to offer a particular tint (WC, for example). I've no idea what degree of sorting SF does but my two lights could almost be from different tint bins, they're that different. Not what I'd expect in a $150 light.
Take it apart....LOTS of heat.