Clayton carries a mini-mag, and shows how to avoid losing them, which is a handy suggestion, since I lost a few when I used to carry the mini.  A few years ago I switched to carrying a Surefire 6P. Not only is it a lot brighter than the mini, but it has a holster that completely secures it, and there are a number of tactical holster makers that make holsters for it.
Downsides are it takes a more expensive lithium battery, which won’t last long if you keep the flashlight on. The Surefire isn’t really meant for continuous use either.  It’ll get very hot if you run it more than 10 minutes.  The nylon Surefire holster also doesn’t perfectly protect the button at the bottom, and I burned a hole clean in the top of the flap that covers and secures the flashlight when I sat down on the button one time.
It does, however, do a good job of hiding the Glock if put at 3:00 with the Glock right behind it at 4. If your shirt blows open, you’re not made. It’s also bright enough to night blind someone if you aim it at them.  All in all, I doubt I’d go back to the mini-mag. For those that don’t carry a flashlight, I would highly suggest it. In my line of work, I’ve always found it handy anyway, but you’d be surprised how often it comes in handy in other situations.