Siglent has changed a lot in relation to the earlier SDM3055.
No more rust on the cut edges / punched edges.
PCB changed (components that have been subsequently soldered on now have their own soldered joint in the pcb).
The quality of the bcb soldering (Dave complained in the 2015 video) is now flawless.
Siglent replaced the old fan with a higher quality one (lower speed, quieter bearings, quieter blade shape, diameter now 60x60x12 mm).
In addition, the voltage for the fan was reduced to 9.4V.
The plug connections flat plugs (e.g. earth) are firmly attached with clamping force.
Negative changes:
The sd card slot has been rationalized away.
Unfortunately, in order to further reduce the noise of the fan, an unsightly remedy has been used.
The fan has been installed "upside down", which makes it even quieter since it sits so close to the grille of the cover
(since it is now no longer on the suction side but on the pressure side of the grille),
but this has major disadvantages in terms of flow technology within the housing.
If it had been installed with its suction side at a distance from the grille (8-10 mm would have been enough),
it could have been installed the right way round without amplifying the noise.
I will change everything (already started) and build a temperature control with heating and ventilation,
adjustable from 20-35 degrees Celsius in steps of 0.5 degrees, the set temperature then remains with an accuracy of +-0.25 degrees.