Hey Steve,
I’ve been an audio enthusiast for close to 45 years now, and for the time being have settled into a pair of 946 Focal Electra for a few years.
Pertaining to your question, "are Focals a clear upgrade path OR are they short term speakers that wow the listener early, and fatigue in the long term"?
Ans: Focals can certainly be a clear upgrade path. To what extent depends on what’s infront of them, and to a huge extent the room they’re are being played in. I use an Oracle Delphi table, with a highly modified RB300 arm and a Dynavector 20X2 cartridge. It’s fed into a Audion Premiere 2 box Silver Night, pure classe A, single-ended pre-amp, using Siemens E88CC tubes. My amp is a stock Classe' Audio DR9.
Are there more esoteric systems? You bet. Could the room be more optimal? Yes. But all in all an excellent platform for any reference system.
If you’re auditioning them, or use them with high volume, mass produced, big box store electronics, the clear upgrade path becomes opaque."Are they a they short term speakers that WOW the listener early"?
Ans: Hardly. If anything I find Focals mundane. The reason being is that they’ve been engineered to be linear. Nothing jumps out at you, they’re not an in your face speaker. They are subtle, laid back, smooth, even, transparent, with a defined sound stage and good timbre; yet when the music calls for it they’re dynamic (if you have a good amp).
This why the 946 Electra is a long term speaker, they do everything right, they predominately sell ya steak along with the sizzle, not the other way around.
Why so many used focals? That calls for speculation, but 1 reason is that with audio buffs the grass is always greener. We are an incessant breed.
Cost no object would I trade my system? You bet!!! The Muraudio px1 speakers are the nicest set-up I’ve ever heard. Drive them with by a pair of Pass Labs xs300 amps, with a new Wheaton Tri-planar mk8 tonearm on my Oracle with a new set of Telefunken 6922 tubes in my Pre-amp, being played in a 20ft wide x 36ft long room with a 16ft ceiling and I’d be a happy camper. - - - Which leaves us with .... when is enough, enough?