I did a workshop at MABS. The teacher came around to observe/advise on pruining my tree. He handed me his concave cutter so I used it. It was a SS cutter and I couldnt believe how light it was and it cut very well. I tried using mine (cheaper tool, carbon steel) and I was instantly no longer happy with it. I should probably try sharpening them, but Im not sure the best way to do that.
Later that afternoon, I went and upgraded my concave and nob cutters to SS ones. Not sure what brand they are because I cant read the writing on the package....lol. I paid $40 to $50 for 8 inch cutters.