I have and use a few Challenger tools, along with mostly Proto and Blackhawk. Challenger tools were excellent. Not really tool polisher items, but good solid tools. Blackhawk have been good to me as well; I enjoy using them and they are a bargain. My long winded experience with late-production Challenger and what happened to the brand is described below. In my industry these mid-priced tools are more common than Proto or Wright. I'm no expert, just relaying what I know and what I think.
I have (somewhere) a Challenger catalog and price list from 1998, so they were produced at least until then. Around that time I bought a 3/8"-drive SAE standard and deep 12-point socket set in a red metal box, with a ratchet and two extensions, that I still have. I loved it when socket sets came in metal boxes or trays. The Challenger sockets and extensions from that era are the corporate Stanley sockets and extensions that were being sold or rebranded (as Stanley Professional, Husky, Jensen, Wilde, etc.) around that time, and the ratchet is identical to a couple Blackhawk USA ratchets that I purchased much more recently, around 2010.
Based on that Challenger catalog and a Proto catalog that I received at the same time, as well as my memory of Proto's website from back then, Stanley was marketing:
Proto as the heavy-duty, full line industrial tool brand
Challenger as the medium-duty, partial line industrial tool brand
Mac as the heavy-duty, full line automotive tool brand
Blackhawk as the medium-duty, partial line automotive tool brand
Evidently in the early 2000s, they dropped Challenger and moved Blackhawk into Challenger's former position under Proto, and Blackhawk is no longer promoted as an "automotive" brand. I'd imagine this is at least partly due to mom & pop parts stores largely disappearing and chain parts stores switching to their own, less expensive house brands.
It's interesting to me that all the Blackhawk sockets that I have that were produced under Stanley appear to be different from both the contemporary Challenger sockets and Proto sockets. All three were always USA-made, and since Stanley bought the National Hand Tool cold forming plant in Dallas in 1986 all three were probably produced in the same place, but yet Stanley kept all three lines' sockets distinctive, even when they were producing Challenger, Blackhawk, and Proto at the same time in the 1990s. Even today the Proto and Blackhawk sockets have distinct design differences - the Proto sockets are generally taller than the equivalent Blackhawk sockets, and the Blackhawk SAE sockets have a tapered drive end in the larger sizes. I suspect the quality is probably essentially equal, but find it interesting that they are making a distinct socket design in the USA that is only sold as Blackhawk, a brand with pretty limited distribution.
Please help, I cannot find this anywhere. Specifically, the number L6112P I cannot find on listings for sale or Alloy Artifacts. Thank you.