I have a DC4, and I'm impressed by it. Works fast, and the ceramic side is the most aggressive I've seen (compared to other ceramics, like Spyderco). The ceramic side feels very different (rough, actually), but works surprisingly well. As with any diamond or ceramic hone, use it with very light pressure. Bearing down too hard on it will be counter-productive, and will also scrub excessive amounts of diamond off the hone, shortening it's useful life.
Having said the above, my first choice for sharpening and maintaining such a knife would likely be the wet/dry sandpaper on a firm, but forgiving, backing (like leather on wood). You can pick & choose which grits work best for your needs, and both the block and sandpaper can be cut & sized appropriately to your knife. Very inexpensive, too.
One reason I like using the sandpaper method, it's done with an edge-trailing stroke. The downside of using a pocket-sized hone free-hand, it's pretty easy to get 'bitten' by the blade, especially with a large blade on that small surface. Doesn't take much to run the edge off the end of the hone and bite a fingertip or a knuckle (unless you lay the hone down, but you have to keep it from moving somehow). I'm all for developing the skill & touch required for free-hand on any device, but the edge-trailing stroke used with the sandpaper keeps the edge moving away from the fingers & knuckles.