Because I'm more a collector than a user, I haven't sharpened any of my 154CM knives. D2 also has a reputation for being rather hard to sharpen. My pocket knife is S30V -- I just run it along a pair of crock-sticks a few times to refresh its edge, and it's good to go.

What exactly is the issue with sharpening the other steels? They both have high "wear resistance" ratings, but they don't seem to have hardness ratings that are higher than other good knives, something in a 57 to 62 range, usually targeting 58 or 59. If I ever do decide to make one a user, perhaps I'll experience the same difficulties, but I'm OK with ceramic sticks for now.