The 600 df is good. I have a modlite plhv2 I like alot as well. Lights are pretty similar with the PLH throwing a little better and the 600df having similar intensity but slightly wider spill and better illumination out to the edges of the spill. PLH can use the same surefire rear caps and has a single 18350 or 18650 size model.
Now shipping the new, slim heads, as shown in the primary picture. This light package contains a PLHv2 light head, 18650 or 18350 body, and your choice of tailcap. It also includes one 18650 or 18350 cell and charger. The PLHv2 head is rated at 1350 lumens and 54,000 candela, which provides...
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I have the 18650 version. Whichever version you go with I highly suggest sticking to a single cell solution. High output lights can cause a fire if one batt is dead and the other has charge when the light draws load. Has to do with the dead/low cell trying to rapidly charge and equalize with the full cell and internal resistance causing them to heat. Charging two 18350s means you need to be sure they are both correctly charged as a pair before you use them. Good batt chargers have indicators for this. Single 18650 or 18350 dont experience this potential issue and in a pinch an 18650 light can just run two lithium cr123s-- edit to add, some 18650s can. The modlite cannot and the surefire 600DF can