Mmmjm the misconception is that 999 Silver IS more conductive than Copper, but when vendors sell you a 'Solid Silver' part they are normally selling you a sterling silver (.925) or 0.96 Silver part. Both are so close to Copper it makes little if no difference.
the contact ramping up faster has nothing to do it with it. The contact's role is to pass the current to the next part in the series of conductors until it hits the coil. these are VERY short parts and the speed of current flow on a 0.5" pin made of copper or silver you wont notice. specially since before or after the contact you have other materials or much less conductivity involved, cant be faster than the slower part (referring to negative contacts in this case)
A LOT of it is placebo, there are small improvements, silver does require a lot less maintenance than copper though unless you live in the coast.
A solid silver RDA pin or solid silver positive post (or both) would be the best improvement
Something like this puppy (some day!!!)
https://www.platinumvapeshiram.com/products/solid-silver-battle-deck
things like the culverin, kennedy and so on rdas you can buy solid silver POSITIVE pin or post, no point on the negative post since what it sees current wise has to pass though the 510 / mod body (aluminum, brass, copper, SS), negative contact
Yeah if you can buy the solid silver slam piece for $4k for a 5%? improvement in voltage be my guest. I personally like clean mods without all the engraving around (the most I can take is the purge twistd or kennedy vindicator)
Reason I'll never buy a pilak, just find the engravings distasteful. Can have all the silver you want but I want a CLASSY design, not some naked women engravings and cards symbols.
This one can be all the silver and all the 4k you want, not for me either:
https://www.modernvaporcompany.com/copy-of-purge-mod-slam-piece-black-plague-edition/