I've only ever used a Sharpmaker on my CRKs, and it's worked great. My first Sebenza, bought brand new back in 2002, was extremely dull. The edge came so obtuse out of the box that I could press my thumb on it and run it lengthwise along the edge with no danger of cutting myself. At the time, it was my most expensive knife, and I was afraid of ruining it, so I used the medium rods on my SM to reprofile the edge bevels. Admittedly, it took a long time, but I didn't care, because I was afraid of removing too much metal at once and possibly messing it up. I eventually reprofiled the edge at 15 DPS and finished at 20 DPS. I've never owned the Spyderco Diamond rods.
I'm not saying the SM is the ideal tool to reprofile a knife, but I am saying it is indeed possible, because I did it. I also completely reprofiled the edge on an ATS-34 Benchmade Stryker that came similarly butterknife-dull. Are there faster and more efficient systems out there for that? Of course. I just don't own any of them.
All my other CRKs came sharp out of box, and have been very easy to tough up on my SM, even though CRk's edge bevels are convex.
Jim