Berea & Craft Supplies still have plating durability/wear ability charts at their web sites. Durability & wear ability have been discussed right here forever.
Pen Kit Making Supplies Berea HardWoods
Pens and Platings - Craft Supplies USA - Craft Supplies USA
Consensus here has always been 10K, 24K, & upgrade gold not the most durable platings. Pretty much what those charts tell you.
Think the only thing vendors will do for you are exchange or refund purchase if they make a mistake, parts missing, or quality not what you expected. Each vendor handles problems differently. That is why you insect kits when you get them and be attempting to make them. If there is any problem with your order notify the vendor immediately. After the pen kit is made not sure they will do much for you.
Having said that, seen here where if enough people complain about problems with kit components vendors trying to solve those problems. Cannot remember kit names but think enough folks here brought component problems to attention of Berea & Craft Supplies who in turn went back to manufacturer or provided a work around to get problem solved.