The fans are louder than I had anticipated – but I guess I should have known that, so that is probably on me.
However, the amp I received added distortion to all channels (as was apparent by feeding it with a simple 440 sinusoid, and comparing it with other amplifiers, same monitors). I assume this was a flaw in my specific amplifier; in any case I have just returned it and decided to move towards the MK II models (with no fans).
Thomann was perfect, as usual, with customer care and return policy.