I was picky about laptop keyboards and it eventually affected my choice of external keyboards as well, but I couldn't find one with a 75% (or at least standard full-size) ANSI layout, good quiet scissor switches and solid non-glossy case. I somehow knew there was MS Natural, BWU, SS 6Gv2, Leopold and maybe IBM Model M—and I knew there were people using vintage keyboards. I started to hoard old stuff too, because the new stuff I found in computer stores was disappointing.
The very first five kinds of switches I tried were complicated white Alps, Cherry MY, Amstrad linear spring-over-membrane, Cherry MX Black and finally Cherry MX Red, the first one that I really enjoyed.
Surprisingly enough, I'm back to where I started, after having tried dozens of various good keyboards with all kinds of switches *and* layouts. However, I can type on anything, unlike when I started with keyboards. Most time is spent on Cherry MX Black or scissor switches and more importantly, a custom matrix layout.