The performance of any mechanical mod is dependant upon the efficient completion of the electrical circuit.
If the switch mechanism is functioning crisp,positive, and direct and the atomiser connection is neat and flush with most (in the perfect world, ALL) of the mechs positive pin connecting with most of the atomiser pin, then voltage drop (or loss) will be at a minimum. Skew whiff connections, both with the negative firing pin and battery base, and mod positive pin and atty positive pin, are common place amongst cheaper clones. The material used in construction of the mechanical mod (stainless, copper, brass, etc etc) will not correct production faults.
Machining quality makes all of this happen,or not happen, something we have to live with when it comes to cheaply made, mass produced 'clones', and something we have to accept if we want 'cheap'.
For me, the odds on getting a 'good 'un' through the post, when weighed against purchase price, are always in my favour, so the click on the 'pay now' button is a pretty fair gamble.
Assuming that construction of the mech is good with everything connecting as it should,voltage drop will be at a minimum and the benefits of copper versus stainless will be negligible.
I have three knock off nemmy's, two stainless, one copper. The copper out performs one of the stainless, but does not hit has hard as the other stainless.
The variability of clones!
I suppose the bottom line is that it's whatever you fancy. If you like the looks of a copper mech, get one.
