I don't have any of these but I have looked at all of them. The Caly is a beautiful knife but my Sage 1 is easier to open with a larger hole, plus I like liner locks. Techno is cool but I didn't want to spend that much when I was shopping around. I myself am looking at getting the G.B. Air because of the M4 steel, the light weight and I like the glass fiber scales. All are very different knives, so it's just about what you like. Techno is definately not a gentlemen's folder, but if you like a sturdy beefy little knife, it would be great. Calys have been around for a long time and they're elegant and good EDCs. Air is a wharncliff which some people don't like but it's a beautiful knife with great blade steel. If you choose one of these and don't like it, don't sweat it and just buy a different model. Thats the thing about spyderco, there's something for everyone.