Like Bmoney, I have a guitar for sale that might be interesting to you.
Mine is a 512ce 12-fret from 2017. It is a re-voiced version of this model. It's listed in the marketplace here.
I've played the 812 and the 512 (and the 312). I played both the 14 fret cutaway and the 12 fret cutaway versions of the 800 series and they both sounded really fantastic. Compared to the cedar top I have, they are definitely a different voice. The spruce top is louder, and has more power and top end sparkle/brightness for sure. And the 12 fret version added a lot of bass compared to the 14 fret version I played. I think the 14 fret was a little bit more articulate, and you could strum on it harder, but I definitely preferred the sound of the 12 fret.
The cedar on the 512ce 12 fret I think has a sweeter, more rounded voice to it. It's warmer in tone, and to my ear, the bass kind of blossoms and fills out the sound with a relatively long decay. It responds to the lightest touch. Seriously, you barely have to touch the strings with your fingers and it rings out. It does have a lower ceiling for strumming than a spruce top, though. You can strum on it for sure, but if you're heavy handed, you'll likely appreciate the headroom of the spruce top.
Both the 500 and 800 series sound amazing, but they're a bit different in voice. So it depends on what you're playing it for. I can't comment on a 600 series, as I haven't played one. But aesthetically, they are my JAM.
One thing to consider when buying a 12-fret is the cutaway. If you're playing up around the 12th fret, or if you ever capo mid-neck, you may want to take that into consideration. I somewhat prefer the look of a non-cutaway. But with the 12 fretters, I'm always glad to have a cutaway, as I capo at 4 and 5 a lot. You run out of fretboard pretty fast if you move out of open chord position.