B4 GRID 110KG (I.C) - Akadot Retail
This paper is great in all areas. It's been great with my traditional pen nibs and ink: the nibs won't scratch and the ink won't bleed through the paper. The only confusion that came up was where to draw on the paper to account for the cut-offs that come with the printing process (the instructions are all in Japanese). Before you start drawing your manga, I recommend you look up the English translation of the diagram on the back of the front page. :)
I've used this stuff for a good while now and it's perfect. The GRID helps alot if your not one to that good with a ruler. The size helps alot if you want to details so I recommend it.