I got to briefly intercept one of these silverburst Epis. It was a nice player. The bolt-neck Epis have a much chunkier neck profile, but I kinda like variety in necks - so I get along well with them. Nokturnal has a Goth (maho body) that I quite like too. The latter has the more aggressive, slightly overwound-sounding Epi TB pickups. The silverburst struck me as more of a jazz bass sound, with its mild-mannered guitar pickups (six polepiece PAF-clones visible underneath). A good serviceable sound, just not the Tbird sound I'm used to.
If you can stand the Thunderbird ergonomics (I think they are comfortable, but they're not to everyone's taste), I agree with dadagoboi- check out some of the other variations too. I haven't played that neck-thru Epi yet. The Gibson has a sleek, slender neck profile and given your love for Rics you'd probably enjoy the complex, bell-like mids. You might not get to try without buying first, but the mahog set-neck Japanese Epis/Orvilles/Elitists are BEAUTIFUL and sound slightly different in their own ways too - but still very "Tbird". I love the thin bodies and Gibson-profile necks on these. You can tell they modeled them closely after the 70s RIs:
76 on left, Epi Elitist on right:
Back to the silverburst- I tried making a recording of the one that I played here:
. I wiped the bass from a Kraan and Meters track, and played along (pick and fingerstyle, respectively). Bass karaoke. Not a great recording, but might give some idea of the sound with fresh strings a half-ass setup (it arrived with no attention paid to the setup).
There is a thread here with more discussion of that model too, if it helps:
http://bassoutpost.com/index.php?topic=2604.0