Quick and Easy way? sure .... cheap? hell no.
Take the kits you have questions about .... and DESTROY THEM.
I mean it, literally ... see what it takes to break the kit and wear away the finish. Final test, take a newly turned pen from that kit line and RUN IT OVER WITH YOUR CAR to see the damage.
If you really want to see the quality of workmanship and protection that the parts actually have, your only real choices are to take someone's word for it (like the manufacturer) or to destroy the kits yourself to make the determination.
My method of choice would be to take the kit over to my belt sander and grinding away the finished surfaces of the parts to see just how thick that plating REALLY is .... Once you know that, and can compare to the cheaper or more expensive kits, you'll know who's putting out real quality and who's not playing ball....
But when you really get down to it, does it really matter? A pen is a writing instrument, not a weapon to be used in a battlefield. The plating thickness, as long as it holds up to it's environs and it's owner's treatment of it, is irrelevant. If they are grinding away the finish to see how durable it is, I'm pretty sure that that kind of abuse is outside the warranty (implied or otherwise) for replacement/repair free of charge ...
On the other hand ... when they walk into your shop area or display area and see pens that YOU have subjected to such treatment in order to show THEM what the pen is really made of inside .... well, that's just a way to ensure that your customers understand and appreciate the pen components and may help them to understand how best to protect their investment. (Also shows that you are committed to discovering the best quality you can find for them .... or that you need to be committed for wasting money, in your wife's eyes ...
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