The Brice Z6 models look promising. If you get a bass from Rondo Music, let us know how it checks out with a little review.
They are promising - especially when you take out the electronics, shield the cavity, and drop a Bartolini pre-amp in it. Here's me playin' it:
And me with my Brice V2 six string fretless that they don't make anymore. For $199, I can't believe the sound I get out of it:
Hear what they sound like by clicking the myspace link in the signature.
And from one extreme to the other - here's my Adler:
