I did some writing on Levenger Storyboard Paper. The paper seems very rough (the nib drags in it), but I didn't see any feathering. On Rhodia Web Notebook paper, the ink shows no sign of feathering but takes a few more seconds to appear dry. I wouldn't hesitate to use it on Levenger Circa paper based on this preliminary experience.
Many thanks for letting us know about yet more experiences with specific papers.
Due to the fairly low lubrication, I think most of those not familiar with i-g inks could well be adverse to any papers that do not have a smooth finish. It is my tendency to use Medium and wider nibs with i-g inks, partly to show-off the shading. Perhaps a textured paper + a narrow nib can be off-set by using less pressure - a very light hand. The line quality should remain high, as shown on the HiRes images on the G Lalo and Royal.
I agree about the dry times - certainly not a fast dry ink on the harder surfaced paper such as Rhodia. Even the first of the photos which show the change in tone & colour after writing show wet ink glistening (click on the image), and that was perhaps 5-ish seconds elapsed from writing until Cathy positioned her camera and got the photo. IIRC, the paper was HPJ1124. (Believe it or not, the letters are 'str' from the word Registrars).
I'm not sure if using a blotter would be such a good thing - it would certainly soak-up any wet ink, but that may also change the appearance of the shading. IMHO, blotters are best used on more saturated inks without shading. e.g. PR American Blue, Diamine Majestic Blue.