Use a Kick on my Silver bullet. Never failed me, always consistent. Takes a bit of tweaking to find the right watt's for you and/or your juice and to figure out the little dial, but once you dial it in, you never have to worry about it again. Always right on the money and has a shutoff to let you know your battery is hitting that point. no voltage drop-off's that mech. mods can suffer with either. Just a great mod all around for your mechanical devices.
Basically, consider your mod a Darwin without the fancy stuff.