Re:
I'm currently on the other way, paring down my "collection".
My first mtb was a '92 Trek 950, and although I liked the 970, I could not afford it being just 16 years-old and paying for it with my little savings (my junior account, opened by my father when I was 3 was left at zero afterwards!).
With the years I realized that:
-the 970 was basically the same bike, only one level up in componentry, and with a less cool color (lila instead of my cool shiny black)
-the bike abilities have always exceeded the rider capabilities, so no need to search for a "unicorn".
Now though I have slowly collected different Trek 950's from the early 90's: one for my wife, one to leave at the in-laws for those weekends when we visit them, and one at my parents. Enough.
I see that pattern in many in this forum. Our first bike was from brand XX for whatever the reason, and we start collecting bikes from that brand/year/range to "expand" our fond memories of that bike, no matter what the rest of the world think about them.