I thought this was pretty cool as museums go. We saw the Greeks exhibit, and the whole thing was very well laid out and well explained. Really, it was super well curated.
The waits were absolutely insane though, and the whole space is surprisingly claustrophobic. The employees were all very nice and informative.
I think this place is DEFINITELY worth a stop if you're visiting Montreal - you will learn a lot about history, and by history, mean OLD stuff.