"@ $180+! are they made of adamantium?"
That's what everyone thinks until they see what goes into making a proper knife, myself included.
Hell, I charge over 200 for some of my fixed blades and I don't even consider myself "great" yet. I'm good, but not great. If I were doing Sebenza type folders, you'd see my charing upwards of 500. It's not easy to make a good knife. There are countless things that can go wrong and only one way for things to go right.
All that said, if you're looking into higher tier folders, a Sebenza is the way to go.
For economy, a Spyderco Tenacious is wonderful. I carry mine daily along with one of my own fixed blades. Just don't expect the 80crv3 to keep an edge forever. It's not the greatest steel in the world. But for 40 bucks, you shouldn't expect something in 3v or hitachi white.