Depends on your end-use.

I have a couple of petzl e-lites and a black diamond duo tucked away for emergencies. They are led, have great battery life and are good enough to use at a campsite, to read by, or to illuminate your hands while doing detail work, or to use while walking (slowly and carefully) on a trail at night. These are very small and use watch/hearing aid batteries.

A step up powerwise is the tikka and tak tikka xp. The tikka has multiple leds and while the taktikka has only 1 high output LED (but with a focused lens which makes it brighter). These use AAA (or maybe AA, I forget) batteries so they are easy to replace. The taktikka has a power boost mode that is good for looking at things at a distance. If you go with a tikka, I would strongly recommend getting the newer version where the switch is a pushbutton sealed below rubber instead of the older sliding switch version. I got sand in a sliding switch mechanism and that louses it up.

The petzl myolite 3 has a xenon and 3 leds so it is a good all around light. Battery life on the leds is great and with the xenon it is bright enough to do some trail running or (in a pinch) use on a bike riding on a trail. If you only had one light, this would be my choice. But the battery pack is separate and it sits on the back of your head with a wire running around to the light and some people don't like this set up. It isn't very compact either.

At the "top" of the spectrum, I used to have a black diamond Solaris which also had xenon and leds and it was (at least a couple of years ago) just about the brightest thing out there. However it was still only powered by 4AAs or a rechargeable pack so there is an upper limit to how much light it can throw. And it is not a bright as a "normal sized" streamlight flashlight.

I got the Solaris to use going to and from duck blinds through marshes in the middle of the night and was disappointed with its brightness and went back to carrying a hand-held streamlight flashlight for pathfinding and also carry a small e-lite or the equivalent for use once I actually make it to the duckblind.