I have an Endra Clipit that has a full spyderedge. It's great for cutting cord,rope,zip ties, etc.. I find that a tapered DMT rod works better than the sharpmaker on the serrations. I'm not a fan of partial serrations, but find the full spyderedge to be very useful.
I have some of those tapered DMT conical diamond rods myself and I do find them to be very good for seriously banged up serrated edges. Or if your scallops need serious reprofiling which doesn't happen too often. DMT also has some conical ceramic rods which work on some serrated sharpening jobs and I have 2 of those also. I do have a lot of respect for DMT's product line because their quality is really good on most of their items.
Like I've said before I am a huge fan of the Spyderco 204 Sharpmaker for many types of sharpening jobs but not for Spyderedges. I do know that the Sharpmaker will indeed sharpen a Spyderedge but I don't like the after-affects it leaves>> so I do the vast majority of my serrations and Spyderedges with the Spyderco 701 Profile set. ON most serrated sharpening jobs I find the Profiles to be the very best way to get them razor sharp. I've yet to master the Duckfoot and Goldenstone sharpening tools of Spyderco's because I do need to learn more about them. I'm looking forward to learning more about them as information becomes available.
Also the 3M company has some really nice diamond sharpening tools as well.