I took a metal cutting saw blade and turned it into a 5" blade.
After sharpening, I was able to shave with it.
I think it will hold the edge for a long time, because I am not going to cut metal with it.
Acutally, because the blade is made of bi-metal. The body is made of steel which is stiff but flexible and the edge is steel tempered to be extremely hard to hold an sharp edge.
I was playing with it yesterday. I was able to slice pork chop paper thin accross the grain.