They ARE the best fretless on the market IMHO, followed closely by the Steinberger XL2A. Replace the barts with something more hifi though if you like your mids and sparkles. Change the pre to one with sweepable mids for extra control.
Superb build quality, incredible necks, each one is hand made. Very low production volumes each year. The Wals are slightly growlier thanks to the mahogany body but lack the same sustain.