I disagree about the thicker paper part. It's the "sizing" of the paper that's important, that's the preparation of the paper that makes it more or less absorbent. Moleskine/Lechturn and similar notebooks have a sizing on the paper that makes it less absorbent and easier for a fountain pen to glide over. Printer paper is way more absorbent and creates more drag causing you to use more effort. Source: I use a cheapish but decent Lamy fountain pen on both kinds of paper, and I write cursive and shorthand for speed, but print for long term legibility.