The weights in all Noj sets are the same and not too heavy. I have never heard of any of their pieces cracking at all.
Fischer had a set that was not weighted. You can see videos of him on the internet handling and moving the pieces. Some people on here have bought their Noj sets unweighted and they are happy.
My Dubrovnik Minceta is weighted and it’s great as well. You will also find people on this forum that have weighted sets and are very happy with theirs as well.
Sorry to not give you a solid answer one way or the other. For what it’s worth I would get mine weighted again in a heart beat.
In your opinion, which one is more fun to play with? Why? Also, are weighted Noj pieces more prone to cracking?