By their website, there is a lot more than wood in a nobile core.
They have a good rep and I have not heard of them breaking a lot.
I would not worry about it.
More thread drift:
Core impacts frequency response/damping/ride quality.
In all-wood or wood core/Eglass boards, core is not as separated from the skins in function as in foam/carbon etc. boards. Machined wood core responds differently to hits in different areas... I make hollow wood boards, they work a little differently from nobile (like -not as well
), and definitely weigh more at 2.8-3.3kg
Too bad about the weight, but I get a good flex and ride without having to buy nomex, carbon, kevlar, rubber sheets, etc. Just 3 and 6mm birch ply....
Here's a pic of a rough-cut core next to a similar finished board: