I recently traded a Sterling 2HH for a fretless Mania.
It plays soo nice...really well balanced, lovely neck, great tones.
Possibly the best fretless I've ever owned.
You also have to account for the finish. The amount of time spent on finishing anything is an important factor - that's why hand-built basses have an extra 0 on the end of the price.
Somebody posted info about these in a different thread - drawing a comparison with the Wal sound. I'd really like to know how good they are.
https://lusithanddevices.com/product/nfp-single-jazzplate/