I found in my notes that they were still making the
"Super Razor Blade Stainless" series in 1980.
As for collectability - it's pretty much like Phil said.
For the most part - folks like the solid construction "Frontier"
series by Imperial. There's a few of us that collect the colorful, hollow
handle ones (shell handle)... just for the colors alone! And also the
early solid construction bone handle EO's and military utility knives are