I have some older sk sockets that have stood the test of time well.
I recently bought some sk impact sockets and those look to be great.
I also recently bought some sk chrome sockets and while I'm sure they will function well, there are interior rust issues and spots where the chrome coverage is missing. Personally this is not a big deal for me as I intend to use the sockets and they will get scratched up and get gunk on them.
Reading on this forum it appears that there was some issues with QC before sk went into bankruptcy. Not sure if what I got was pre or post bankruptcy production, YMMV