As far as ordering an Alembic without ever having played one goes, I offer the following ....
I bought my first Alembic, my '84 Spoiler-Exploiter, via Ebay.
I bought my second, my Spyder (#7) without ever having played it.
Finally, I bought my Europa without ever having played it either.
On the first one, I had no choice. On the Spyder, I knew it was going to be great (and it is) based on the first. On the Europa, I knew it would be great since I'd played an Orion, which is similar (though not the same, I realize). In all three cases I was more than satisfied.
Bottom line is Alembic has a reputation, and folks are willing to pay for that sight (and sound) unseen (unheard). I've not been disappointed, and suspect others haven't been either.
Just my two cents,
Alan