yes, it seems the thread is dead - the silicone plug seems expensive and troublesome without a gaurentee the silicone will cure completely - and it won't work for eGo Mega cartriges (or eGo Type B cylinder carts) without something to keep the silicone plug from working it's way up into the cartridge, something like the hollow tubes they were putting through the vent holes (which increases the chances of leakage)...
eGo Mega/cylinder: the coffee straw mod works well for topping off the Mega cartridges (but with the tip pointing up the atomizer will flood easily immediately after topping off, or after a long period of no vaping - later, after vaping about 1.5 ml, the atomizer will be too dry after a long period of the tip pointing down). fresh polyester filler is cheaper than washing used filler with grain neutral spirits (ever notice vapor coming out of the filler when you top off imediately after it starts tasting dull? maybe you need the straw mod to see it? i wonder if the dull taste in well-used unwashed-filler comes from vapors condensing on the fibers). for now, i'm using tweezers to make the filler dense and wet by pushing it down and then pulling it up flush with the edge of the cartridge, adjusting the straw if necessary, topping it off, and then putting the atomizer on it while keeping the tip pointed down for the first 5 or 6 hits - i'm finiding the first 1.5ml is good vaping, after that the tip needs to point up for some time for a good clean tasting hit. (i've run the wick dry by using centripital force to make the last of the fluid in the wick move towards the atomizer - it doesn't take much - for each draw, maybe one, maybe two hammering motions with the tip towards you).