I am using a new Canon ipf 6400 and bought a 24 inch wide roll of Hahnemuhle Photo Rag Pearl 320 gsm, after trying the smaller sheets of this paper. I have learned that I cannot use the media type suggested by Hahn. in the literature; I had a result of severe rub marks of lines for about three inches wide only on one side of the print, all the way down(28 inch length). I had used Media Type Special 5, as Hahn. recommended. I also created a custom media, which I will not be able to use either, since that resulted in bands also.
I have found a solution; I used the media type "Canon Premium Semi Glossy Ppr2 280" in the printer driver AND on the printer control panel. My resulting print, a test of four inches long by twenty four inches wide, was fine with no banding or rub marks. So I feel confident in saying that this result would apply to my original print of twenty four inches wide by 28 inches long with no banding or rub marks. (I did numerous test prints of various settings, after my original print result with the severe rub marks of line, really bad). The print resulting from the media type of the Canon Prem Semi Glossy 280 gave fine results with no banding or rub marks.
Thus I will be using the Canon media type listed above, for prints with this paper, rather than the suggestion from the Hahn. literature of a media type of "Special 5"- did not work well.
Good luck to others, just trying to help based on my output with the settings suggested by Hahn.
(I do use the Hahn. icc profile offered on the Hahn. site, with good results).