MUJI loose leaf A4 graph paper. Slightly off-white and very lightweight, but with zero bleed through, even with thinner fountain pen inks and felt-tips and brush pens. At £2.95 for 100 sheets, it’s great quality and value for money.
The paper quality is like-for-like in smoothness with Midori’s MD paper pad, though at £9.95 for 90 sheets, MUJI is definitely the cheaper option.
The satin-smooth surface of both papers means that even with a really scratchy dip pen nib or fine pencil (I normally use a rotring 600 0.35mm Japan spec drafting pencil), the paper fibres do not catch the tips of whatever writing instrument you’re using.
Both papers are great for general writing, but with the 5mm grid size, they’re also great for kanji drills and JLPT revision.