I have a clone, no heat from my button. If it hits fine and you get that heat only at button then your build is probably fine, as a short should heat the entire battery(dangerously). Have you tried cleaning up the sides of the fire button as well? Did you check your build with an ohm meter? Id highly consider contacting the vendor if everything checks out but its not firing right.
As far as the clone goes, with mine im loving it(i got it from Vaportek). I dont have any full copper mods to compare but i have full brass and ss/mixed. It definitely hits harder, and the size? Well with an 18650 its smaller than any of my mechs in 18500 even. Check it out next to an Evic, both in 18650 mode. The 4nine has my Aqua with PMMA tank compared to Evic with no topper
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