For night hiking, I've been using a BD Icon
for a couple years, and I like it, but lately I've been looking at this Princeton Tec Apex Extreme
. It's 130 lm, uses 8 AA batteries in a remote battery pack (so you can keep the battery pack warm in your pocket), is regulated, and compatible with lithium batteries.
The Icon runs at 1.7W (my measurement) and is unregulated. (The LED has an inadequate heatsink, if you ran it at 3 watts it would burn out.) The Apex runs at 4W (my measurement) and, as you note, is regulated. The Icon has a very narrow beam, the Apex has a broader beam.
I've also been told that it can be used with only 4 AA batteries, although I haven't been able to confirm this yet.
PrincetonTec sells versions of the Apex using 4 AA, 8AA, and 2 CR123 batteries. (I have the 4AA.)
Both of these lights eat batteries and are good candidates for rechargeable batteries. (That is how I run mine--NiMH AA.)
As you note, both lights are relatively heavy and, as a result, I rarely carry mine hiking. I also rarely need that much light.
I normally carry a BD Spot (the PT Remix appears to be very similar) and a PT Fuel* as a spare. The Spot/Remix** give the choice of a 1-watt narrow beam or a lower power broad beam. (The Fuel is similar to the Spot/Remix minus the 1-watt narrow beam.) The 1-watt setting will kill your (3 AAA) batteries quickly and has to be used sparingly. The broad beam is entirely adequate for night trail hiking and camping. Both the narrow and broad beams have multiple intensity settings (so you can trade off intensity and battery life). Any of these lights can take NiMH rechargeables, alkalines, or lithium batteries. These lights are much lighter than the above Icon and Apex. They also eliminate a failure point in the Icon and Apex--no external wires.
* I have an old Fuel--3 LEDs. The new ones have 4.
** I haven't examined the high beam of the Remix. I'm just assuming that it is narrow (like the PT EOS).
The Mammut Lucido X-Zoom also looks interesting, but I haven't had a chance to examine one. I have other lights that allow focus adjustment and it can be very useful.
FWIW, I generally prefer PT over BD for generally similar lights. PT pays more attention to waterproofing (and many of their lights are waterproof). (PT also makes dive lights...)