One of the rubbery strips on my D-Roller plastic apron had a couple of places that were bowed out of straight by about 3/16" at their apexes, exposing the glue by that amount. The glue was on the outside edge so it didn't cause a problem, but I removed it anyway with a blade that I also used to "straighten" the bow.
My problem with the D-Roller was the heavy bar at the core (which is probably the most expensive part of it). Apparently, the glue isn't strong enough to keep the plastic apron attached to it, and glue was exposed where the apron was detaching from the bar. I had to remember to keep my print a couple inches from the core or it would get glued. Much worse of a problem was the undulations on the print that was caused by the weight of that metal core as it flopped around, regardless of how slowly I rolled nor how tightly it was wrapped. I finally replaced the bar with a cardboard core from a roll of all-purpose paper, which still had a few yards of paper on it. The total diameter is about two inches, which is about the same as the metal bar. I glued the end of the remaining all-purpose paper to itself, then glued the end of the plastic apron to that. It's been working perfectly since then and is much easier to handle, with no undulations and no "creases". I suppose a length of heavy-duty plastic plumbing pipe would work fine too. In my experience, weight of the core is a non-issue. For Canson Platine, I roll it moderately tight, let it sit for about 15 seconds, and unroll it.