I own two LED from leatherman. Can't remember there model #, but one uses 3 AAA and the other is a Fenix re-badge AA light. Both are made of very good quality. The AAA is made out of SST, and doesn't last very long and the heat dissipation isn't very good either. Its become a hand warmer very quick. Not sure if this is the nature of AAA lights, but its the only one I own...and it will be the last. The Fenix re-badge one is very good...just like typical Fenix light.
I got an S2 for my fiancee that she keeps in her purse, she seems to really like it. I was eyeing up an S3 for myself but then the local store that carries them increased their price. I'd say their a decent flashlight but priced accordingly.
I got the Serac S2 and to be honest, I don't like the reverse clicky and
the clip is useless, as it has no fixture and will move over the light.
So the light don't fit my needs very well.
On the other hand, the S2 has a decent build quality, a nice beam
and a good output for a 1xAAA light.
I'm very pleased with my Serac S3. I picked it up at Amazon for a friendly price; $46.80 with shipping if I recall. It lists for eighty bucks. The build quality is great, it puts out plenty of light when needed and has fine runtime on a single CR123 battery.
yeti@home
I own a S2 and EDC'd it for a while until I replaced it with a Nitecore EZAA. It is a nice light with good levels of brightness. The only thing I didn't like was the length compared to the Fenix E01 it replaced in my pocket.
I have the S1 and S2. Good lights but the clicky is sensitive so will sometimes flicker at first. But on the positive just a little taps will push these lights into the next mode. The build is good and like the SS bezel.