I had the prototype alder body, maple neck, rosewood board model for a short period. I'm not sure if the preamp in it is the same as the production models will have tho... some comments the bart TCT (?) model will be used or at least optional... I think the one I had was the NT--- model, which I think Mike said was a bit more "modern" sounding.
What I liked...
The tone and playability. It was kinda' like someone took the tone of a 60's J bass, and modernized it, but not in the way of going with a 70's pickup placement. Instead, just adding a modern preamp, and then going through the usual MTD wood selection and matching to give it better "coherence/consistency" and also the usual MTD "alive" feeling in your hands.
I would not directly compare this to a truly classic J bass and say they sound the same, but it's exactly what I would have expected... a modern design, taken a lot farther in the direction of a classic J bass than most other modern designs. Maybe I'd call it an MTD "tribute" to the classic J bass design.
The tone is very even and full, familiar... even with the NT preamp... not sure if the pickups were custom or not. No one characteristic is "over the top" like a lot of more modern designs... it has an identity in the mix, but it's not overstated... extremely "balanced and musical", if that makes sense.
The bass was typical weight... around 9 pounds, very comfy to strap on, classic 34" scale, so a familiar overtone sequence for a more classic bass, and a very pleasant neck profile. Just feels good to wear and play.
What I didn't like...
The fact that the horns are not shaped... give the body kind of a "slab" look and feel. Not my thing.
The prototype did not have a "belly cut" contour, but the production models will, so it should be moot for anyone but me.