yazkaz: I have KL1 running on a VG3 body. In short, I like it!
My options for batteries, each of which I have tried:
1. 3x123's. Get same brightness, longer runtime. How much longer, I do not really know, because I have yet to do some tests.
2. 2x protected 17500's that I got from AW (see dealer thread for his batteries and chargers...) Same brightness, longer runtime. I have not done tests.
3. 2x AA's. Have not done much on this other than a few minutes here and there.
4. 2x rechargeable AA's. Just a few minutes here and there using these.
Additionally, since I have an E2E, I can run the KL1 head on that, too. On either body, the KL1 is a very good thrower. I have used it hiking, walking the dogs, and camping. The VG3 body is fairly light, so I cannot tell the weight difference all that much.
Bottom line: KL1 is one of the very best Surefire products that you can get. Check out Lighthound (
www.lighthound.com) for his products, in case you have not already heard of him or have dealt with him. As for your question about what generation, I am not knowledgeable about that, except that I understand that the one that I have (for about a month now...) is the latest generation.
I say get your KL1 now!
Best regards!