I am not sure where this thread is heading. My interpretation of the OP was like.. what's the one that got away type of thing. What knife did we wish we had pulled the trigger on but never did? I guess the thread has been sufficiently derailed but I'll still post my best response for my interpretation of the question.
For many years I always wanted a Microtech Makora II and a Halo V. I still check them out every so often and especially drool over the Green camo Halo V's. I realize that it's kind of an impractical knife but that doesn't erase the cool factor for me. I had a bad experience with MT customer service once... ends up I don't do business with them anymore.
Another knife that I never owned is one from Randall. They are from my home state and I always held them in high esteem. I like a couple of their fighter models and the small boot knife. Almost pulled the trigger a couple times but never actually did. I believe a Randall or two would fit nicely into my collection.
Other than that I've bought and sold from most reputable production companies, even had some nice customs, and in the end have kept a selection of all of my favorites. I think my collection is well rounded, enough for what I use knives for these days, and really can't think of another maker or design that I "need" to have.
Of course that won't stop me from buying more and more and more as new cool stuff comes out.
I wouldn't worry as much about the Microtech CS as far as the autos go. Most dealers will be able to replace your spring within the week and won't have the shipping requirements that Microtech does. If you had a problem with a liner lock or framelock, though, a dealer might not be able to help you with that.