Listen to the pimp. The function of the "tactical flashlight" is to give you a moment to take the initiative. That's all. Think about being temporarily blinded by a bright light at night--how long does it take you to recover from that? Not long.
But it does take time. It's a little like Ashida Kim's Sissy-Throws-Sand-In-Eyes NHB finishing move, except that it can be applied from a distance.
The REAL function of a "tactical flashlight" is to provide enough light to identify your target in the dark. Identifying your target is paramount when firearms are involved; you can't call the bullets back. It's just that people figure, as long as you're shining a light at someone you think is a hostile target, why not shine it in his eyes while you're at it?
I use a Streamlight Scorpion a lot. It's sort of a compromise between the two types RoninPimp mentioned. It's bigger than most Surefire models, with a relatively heavy battery and aluminum case, but nowhere near the size of a maglight 3D or 5D. It would make a decent fistpack--I think--but I suspect that would be the end of its life as a flashlight. I don't carry it as a bludgeon.
It's not cutting-edge anymore (it doesn't even have any LED's!) but I trust it.