Boosted, regulated, moon mode ???

I'm getting a little confused. Which LED lights are "direct drive," which are voltage boosted ( I assume anything running a single AAA or AA), which are voltage/current regulated, and which have additional battery-conserving modes (moon mode)? Arc AAA, Arc LS, Infinity Ultra, Reactor, Surefire KL1, Inova X5, etc. ???

I would appreciate any information to clear up the confusion. Many of the manufacturers' web sites don't get into that level of technical detail -- just the typical marketing stuff.

I can speak to the three lights that I have.
The Arc AAA uses a single 1.5V battery and is voltage boosted. The AAA also has a moon mode. The Arc LS can use 2xAA or one 123 for 3V. The LS also has the moon mode feature.
The SF KL1 runs on one 123 in the E1e body or two 123's in the E2e body. The KL1 also has a moodn mode.

Moon mode means that the battery has dropped below a threshold voltage. It is no longer able to deliver sufficient power to keep the LED current at the maximum level. Moon mode gives you warning that the battery needs replacing. I hope that this helps.---Marc

Of the 3 LED lights that I'll admit to owning:

Arc AAA, voltage boosted, "moon mode" nice idea, but I don't believe it. It just get dimmer and dimmer... Best pocket light on the planet, though, imho.

Newbeam conversion, boosted and regulated, so it doesn't dim ANY for the first 5 or so hours, then a little red LED comes on to tell you it's fallen out of regulation, and it gets dimmer from then on. Best regulation plan I can think of. As the batteries are near death, light warns you, current goes gradually down with light output, and you get several hours more light.

Streamlight 4AA LED, non-regulated, non-boosted. Very bright, only runs on alkalines (see other threads for bulbs go "poof" on NiMH or lithiums), so it becomes dimmer as you use it.

Ok, I have an infinity, too. Like the Arc, boosted and becomes dimmer with battery use. For some strange reason mine doesn't seem to last much longer than the Arc. I'm guessing a less efficient regulator design in my old model, but that's just a guess. Original infinity much dimmer than Arc.