Although the manufacturer claims that the valves do not need to be lubricated, they do need to be lubricated. valve 3 does not work for my trumpet, because the piston itself is slightly incorrectly molded. It clings inside the cylinder and therefore gets stuck. There are no complaints about the sound, the instrument sounds very good, even though it is plastic.
I recommend for beginners, but needs some work.
Mouthpieces made of plastic are not a very good solution, it is better to use metal mouthpieces. Like a trumpeter, he is pleased with the sound, but not with the mechanisms of the instrument.