Hello to all the CPF members. I'm a newbie and don't know much about flashlights, so please bear with me. I recently purchased an Eagletac T10LC2 flashlight which came along with a pair of Sanyo CR123A Lithium batteries. I have noticed that after 25-35 (not continuous) minutes of use on the high mode, that the brightness level has dropped tremendously low that when I twist the Eagletacs head from high mode (295 lumens) to low mode (60 lumens) there is barely a difference in light output. Now I was under the impression that if using CR123A lithium batteries on this flashlight that my lumens output and brightness on high would be at that consistent light output up until my batteries would just die. Another factor that has raised my suspicions is, that the dealer which I bought the flashlight from, (yes he is an authorized Eagletac dealer) it was his last Eagletac T10LC2 in stock. I hope I didn't get shafted. Please if any fellow members can please enlighten me on what's going on with my flashlight, if it in fact is maybe a defective model or if this is the norm for these Eagletac tactical flashlights to drop in power so much and so drastically in such a short time with these CR123A batteries? Also are the Sanyo CR123A batteries the best performing batteries money can buy, or is there another battery manufacturer (Energizer, Duracell, Surefire, Eagletac etc...) that has a better performing CR123a battery (even if it's just a .01% difference)? I thought that these Sanyo CR123a were the best lithium batteries money could buy. I hope I have posted this thread under the right category and please forgive me for my English grammar, for it is my second language. -THANK YOU