I have no problems with them over the many years (16+) & hundreds (300) of Bally pins I have brought back to life. I have bought about 7000 Mode Electronics contacts over the years, & they are ROSH compliant. I buy stuff from GPE, but I won't buy anymore contact connectors. Don't like them compared to the white ones from Mode or old used Molex ones in Bally pins. I buy Trifurcon contacts from GPE. That's my observations, if others want to step forward please do. I have no idea if the other Chinese contacts come from others or from Mode Electronics. I buy mine from my biggest local electronics parts distributor RAE Electonics.
I can attest that I haven't seen these wear or break down, as compared to the original Molex? ones used by Bally back in the late 70's.
I plan on buying more parts from GPE in the future, except the for the contact connectors. Which I dislike (my personal opinion). They look like a cream color from GPE.
I'm operating old Bally pins also. It was interesting how in the past techs would solder the wires to the pins for reliability (eliminate contacts). When I see this I bring it back to original & use new boards if needed. Earlier days I just replaced with new pins.