Scrapyard started off using steels that Busse had laying around and did not use any more. Also, they would scrounge old handle dies and moulds etc. That's why they called Dan "Dumpster Dan"
Very cost effective knives. High on performance to cost ratio.
Swamp Rat is supposed to be Jennifer Busse's attempt to give Busse a run for their money. They typically use Sr101 (52100 is the more common name with a proprietary heat treat to get the most out of it). Excellent knives, excellent steel. Really a world class steel with super heat treat. Nice handle materials and great ergos.
All great knives. All the same super warranty. You won't go wrong with any of them.