not that weight has any particular significance in and of itself; my heavyweight champ so far has been the Levinson #33 monoblocks. they weighed 365 pounds each. i owned them for two years.
more impressive to me was the magnificent industrial design and the 'commanding presense' that they visually projected. it doesn't take much skill to design something big and heavy.......but to make something that big and heavy that still looks 'right' is an achievement.
they sounded pretty good too.....which was why i bought them in the first place.