I have owned and used both. If i had to choose one or the other, I would go with the
Streamlight.The Surefire is a very nice,small package. It also has a fine pure white beam.But the Streamlight has all of these features,plus it seems to hold up much better under hard use,and it is less expensive to start with.My Surefire would always seem to lose the bulb at the most inopportune times.The Streamlight has yet to let me down, even after I left it on the back of my vehicle and bounced it down the road at 15 or 20 miles an hour!