Agreed, if the Ilford paper is similar in thickness to the Harman offering then the "Thick Media" option need not be checked. Although approximately the same weight, some of the Hahnemuhle papers are physically thicker and may require that option. I am done my "paper chase" for now, time for some custom profiles to replace the canned ones.
I have to wonder if the extremes in temperature and humidity that these packages have to endure after they leave the factory can influence how flat they remain. For instance, for those of us in Canada, it is possible for a box of paper to be left overnight in a trailer or van in freezing temperatures.
As an aside, I am not experiencing any pizza wheel marks with any of these papers like I was experiencing with using more "luster" type papers. Makes the 38xx series of printers more attractive to me now.
Dave