Really interesting question, SnowHot, I gave it some thought.
Objectivity, perhaps? And coming clean as to wants/needs/desires/ability?
The objectivity aspect is a can of worms. Obviously, the skis I demo’d were not “masked,” as they are when reviewed by pros in publications.
I’m not a technoid (not that being one a BAD thing -

). Only know how I ski and what I was seeking in a ski (in the case of my demo night, an all-mountain type capable of light pow/crud-busting). I went in with little knowledge of the skis I demo’d - only that I’d read about a couple of them on the forum and elsewhere and was curious.
That’s about as objective as I could get – the rest was just impression. I tried to ski similar lines each run, each ski, at my personal comfort level. It was an amazing demo experience, as we could quickly switch out after 1 or 2 runs with little down time (over 50 to choose from,

). Undoubtedly, my best demo experience EVER.
When I was on the fence, I took a 2nd run. Did this with 2 of them, just to feel out the subtle differences.
I’m no pro, but I’ve been at this long enough to know how to replicate a run (it was 6" fresh, was easy!) and initiate/follow-through the same type of turn, let ‘em run, etc. I really had no preconceived expectations of any of the 5....I had never skied any of these models prior.
You’ve got me intrigued enough now to want to demo this ski again when/if (hope!) this same demo night is available to me!