I fitted this with Thomastik Jazz flatwounds to get a lovely "woody" tone. It's not a double bass but with these strings fitted you get much the same feel and sound, ideal for working with other acoustic instruments. Unplugged it's pretty quiet (more quiet than a fretted acoustic bass) so you'll probably want a bit of amplification if you're playing with a guitarist. It's a very simple pre-amp, volume and tone only, but the important thing is that it delivers a very good likeness to the acoustic tone with no twangy edge. I also tried it with Warwick tapewound acoustic bass strings which have a brighter tone if that's what you are looking for.
Build quality seems excellent, the satin finish is smart and the setup out of the box was perfect.
Although it's short scale it's quite a big instrument because of the way the neck is set (if you look you can see the bridge is in the position it would be on an acoustic guitar, not where it would be on an electric bass).
Pros - Tone, build, great for acoustic sessions.
Cons - You'll probably need to buy some flat or tapewounds and the Thomann Acoustic Bass Gigbag.