Join Date: Dec 2015
Location: The Very Tip of Lake Michigan
Steve is spot on. I have an old set of Craftsman tools (1950 vintage), and they perform just fine. I suspect they are truly high speed steel (above Rockwell 60) because they take an edge fairly easily and hold that edge quite well. If you are looking at older tools, they are almost certainly the real deal.
But, as with anything from Horrible Freight to the upper mid line tools, the geometry may not be perfect. In other words, ANY tool except the very highest end may need a little bit of re-shaping or re-sharpening; or both. A little time and a little effort can cure that issue. So...
If the edges don't have any obvious chunks gone, if they don't look like they were sharpened with a blow torch, and the price is right, you'll probably be fine.
Another $000,000,000.02 worth of advice,