your right about not knowing the steel or tempering techniques for sure but the way i figure it is if the tool is junk it may be worth the try and you may get lucky. My self i make my own cutting tools, awls and even some of the basic stamps, my mill is a set of hand files lol. If you do buy Tandy stamps then try and get older ones as they were much better quality, same with the cutting tools IMO. Once the mass producing world turned to relying on minimum standards for manufacturing stuff the quality went way down they simply don't test every tool for temper but rely on the sendit back method. I think there is a niche for leather tools made well with no frills but it may not be big enough to pan out.