I've owned a fair amount of basses (still do) but never anything hyper fancy nor vintage.
The Starfire II caught my eye as soon as I saw one, and truly Guild hit the target (on first attempt) by coming up with one of the scant dozen bass models whose tone left a mark in the history in the instrument.
I had dwelled over DeArmond SF basses more than one time, and when the Guild NST SF-II Bi-Sonic came out, I knew I'd been wise by not buying one.
Having no personal experience of vintage Bi-Sonics nor boutique replicas, I find the sound of these Booheung made "lookalikes" very much to my liking. They truly possess a woodsy airy quality that's a far cry from the Gibson "Mudbucker"
Perhaps it's the AlNiCo II, which seemingly is less punchy than AlNiCo V, but I'd rather not get into hair splitting, since there are many who do it better than me. With the exception of high gain contexts, I'd say the Starfire would be comfortable with just about any other genre, and with much style.
It's loud enough unplugged to quickly become your favorite nighttime bedroom bass, and as always with Guild, they do sound pretty great even unplugged. The neck isn't chunky, and its grip seems to have just the right proportions.
The only (relative) bummer is its gorgeous headstock. As much as I love the refined yet sober esthetics, it's too damn large.
The bass itself isn't heavy at all, but that kite at the other end of the neck, when standing, tires my left wrist (which isn't 100%, I admit) a bit more than other basses. I've read that some JS basses have considerable nose diving tendencies (and I guess the others don't because they are heavy as anvils).
PS - when ready to shop, look up AllUsedGuitars on Ebay. They've been having nice deals on open box Guilds for long.