That's a beauty - very similar to my GA24, except mine has gold hardware and the neck isn't bound.
They are great basses, but sound nothing like Alembics. They have a much more 'old school', less hi-fi sound with quite a bit of upper-mid 'honk'. But as has been stated, without exception they play like a dream - very fast necks, perfect string spacing and tension. And those carved wooden pickup covers make very comfortable and decorative thumb rests, if you need such a thing . . .
I always get lots of comments of admiration for that bass when I take it out - more than for the maple-top Alembic MK sig or the Status Kingbass with LEDs - Jaydees are very pretty instruments, and that tobacco sunburst finish in particular.
And yes, they look like through necks, but actually they're glued in. Some people even reckon it's John Diggins' (Mr JD himself) liberal use of glue that gives his basses such a distinctive sound.
The Alembic comparison is purely because of the body shape - while John claimed not to have been influenced by Alembic, I think I read somewhere that the guy who helped him design the shape of his basses in the early days had seen a couple of Alembics and maybe had them in mind as he was giving John suggestions. I also think I read that Mark King bought his first Jaydee back at the beginning of his career mainly because it looked like an Alembic, a bass he was familiar with because his hero at the time, Stanley Clarke, played one.
K.