I used to own the collections (1-6) and remember them being sewn binding and thick. I sold them and bought the series digitally during a sale. When I got rid of my tablet I wanted to get the books again and ordered vol. 1-4 last week.

They seem a lot slimmer from what I remember and appear to be glued binding. I saw on IST they had new printings of the collections and want to ask if they switched to glued binding.