Miche cranksets considered harmful?

I'd give a qualified 'yes'.

I have two sets, both bought used* and both have had various use on track, fixed road and fixed gravel bikes.

I think both pairs have developed a bit of a creak now but no obvious signs of cracking nor imminent failure.

For what I paid for them and the use I've had out of them I'd definitely consider them 'money well spent'.

*I couldn't tell you when I last bought a set of cranks new. Concurrently with the Stronglights I have also had a set of 'bought used' Campy Pistas, which maybe always creaked and eventually the left hand arm came loose during a ride resulting in destruction of the taper in that arm, a set of 'bought used' Dura Ace 7402s which have been rock solid and 3 or 4 sets of 'bought used' Hollowtech 2 cranks which have all been faultless.

TLDR: Stronglights seem to me to be alright, bought brand new and properly installed and maintained I'm sure they'd work and last pretty well indeed.

That said, if you don't need the length, bcd or aesthetics that square taper track cranksets offer then there may be better ways to spend your money.

The cranks themselves yes, but the chainring was terrible in my case - not round at all.

@steelest I've used a Stronglight Track 2000 for about 4 years of year-round commuting, so ~20,000 km with no issues, either ring or cranks. Bought new.