Put some NoAlOx on the threads and the switch and so forth. A guy who used a lot of mech mods on here named Bad Ninja showed me this with my SMPL and although I no longer use tubes the application of NoAlOx is stilla necessity on a mech box. I own two clones of the Cherry Bomber and as long as shes clean and lubed it will hit like a train. Even at higher sub-ohm builds it still hits so good, I have a .5 ohm parallel 28g coil in my authentic Tugboat v2 as we speak and its just such a good box. Dual cell mech boxes IMHO are much better then tube mods due to the lower v drop, extended battery life AND the added layer of safety (some what) at low builds. I got a few Cherry Bomber clones and I just cant say enough good things.
Edit: posted before reading, silly me. What up Bad?