INFI has: 0.5% carbon, 8.5% Chromium, 0.74% nickel, 0.36% vanadium 1.3% molybdenum 0.95% cobalt and 0.11% nitrogen.
see
http://www.ebladestore.com/steel_chart.shtml for other steel.
INFI steel is custom made for Busse. Combined with good heat treatment gives it good performance.
Is it a wonder steel? My guess is that if it was THE most fantastic steel in the world it would be offered for other applications by steel manufacturers.
They don't, so i am convinced that the metallurgist engineers in this world, either don't know their job, or are not convinced that other steels don't have similar performance or they would all start using INFI.
The people who buy Busse are convinced that INFI is the best steel available for knives. That is possible.
But does it warrant the high price? Each it's own.
I am convinced that i could sell 420J steel for 10 times the value to Brittney Spears fans because Brittney spears quenched it with her own urine!
But IMHO some Busse customers have a strong "confirmation bias"
http://en.wikipedia.org/wiki/Confirmation_bias
This bias is supported and enlarged by the other peers who confirm each others bias by gathering in peer groups like the busse forum.
The fact that the resale value is always mentioned could be an indicator that the people who buy Busses have a subcontious feeling that their knives are too expensive BUT that they can always sell it again for a high price.
It seems that the pool of customers of Busse products is rather small and that they support the myth of the INFI wonder steel to convince themselve that they didn't fell for a marketing gimmick.