I haven't seen a Chinese EUB that was Developer with a DB Player in mind. They almost always miss DB Design criteria which arme important for the DB Player like D or Eb neck, bowing, a top that vibrates (for easier start of vibration for bowing) and could take the pressure from common DB strings.
Electronics are often noisy and in many cases they neglect the necessities of a high impedance preamp following the piezo pickup.
Better instruments might be produced in China, but then the design is often not made there.
Setup is often not well made (if at all), so there is still some work to be done to make the instrument playable at all and that might cost at least half the price of a Chinese instrument.
So be careful if you order such a kind of instrument.