Today I managed to make my first mooshimeter firmware update within a virtual machine with android 4.4 x86 on my pc. It worked fine on the first try and the mooshimeter still worked after that.

I used the instructions for android from https://moosh.im/?p=2491&preview=1&_ppp=f573471af3

Nevertheless, everybody has to think for himself about possible risks before flashing from within an emulator.