For books an important features is that the shelves have doors and a back, to have to dust off the books less often. Do yours come with that? I'm not finding that brand on any Swedish retailer from a quick search either, so not sure how relevant it is.

I have some older Billy shelves that have been very solid, even when overloaded with books (I too have a lot of physical books, a lot of them older and not available as anything except physical, quite a few even predating the ISBN system).