I did lots of SETs on Tannoys and ProAcs in the past and know full well their capabilities. Even older recorded jazz on digital sounded mesmerizing.. As well portrayal of acoustical instruments, magical--almost eerily so in their own unique ways of sculpting natural/organic true to life 3D-holographic images--each having its own individual living spaces--great palpability. Yes, the likes of Louis, Ella, Nina to Shirley Horn, Carol Sloane then literally came alive well spotlighted in room during listening sessions--most times, their presence, spooky real!
During that period, circa early '90s, only the FMA 611 managed to slowly lure me away from that SET magic sound--hence kept it for 21yrs+ as my constant go-to/reference amp where many others (SS and tubes) come and go. To me, while they don't lure you to any particular magical areas (to me, midrange stood out for SETs), but rather spread its magic more evenly and balancely throughout entire spectrums.. Ie.Although ultimately missing by a hair bit that SET midrange goodness, they 'overall' portrayed the more natural and complete package, IMHO.
In fact, I found the FMA Resolution Series midrange (vocal, piano etc) to be much akin to SETs/OTLs amp in that they presented them in a more direct/realistic manner than most P/P tube amps I've had/owned.. With better bass and highs to boot.
Anyway, agree when talking audio, there will be endless debate concerning individual choices and I fully acknowledged that there are quite a few great alternates to 'getting-there'.. ;) I'm sure Pani with his vast experiences will finally be able to find what's best suiting him--music/taste/preferences.. Goodluck, whatever it may be, either routes you are currently contemplating seem to be excellent matured ones.