I've used a bunch of different systems throughout the years, and only recently have I begun to understand how they're supposed to be used. My first sharpener I bought was a medium arkansas stone, to go with my Buck 110. I was never able to get it to sharpen the Buck properly, and it's soaking with oil. I like the Spyderco Sharpmaker, and recommend them to people who aren't comfortable with freehand. The Sharpmaker allows for some experimenting with freehand, while still offering a fairly easy 'guided' method.
I got into diamond stones because the medium ceramic stones are terrible for re-beveling. I also used way too much force for the ceramic stones. Then again, until recently I used way too much force with the diamond stones. My diamond stones are some off-brand set. I'm looking to replace them with a set of DMT double-sided ones. I have a small set of DMT 1" X 3" stones that I keep in my pack. They're awesome.
I've been using a strop for a while, and have recently branched out into using different compounds. So now there are three strops. A light touch seems to work much better. But for serious rework or re-beveling, I still use the diamond stones.
I do have a crappy 1X30 grinder that I use to start an edge on my hatchets and machetes. I'm very careful with it, and it's not good for precision work. Still, it does well when I need to pull back the primary grind. I absolutely recommend trying it with various knives that you don't mind trashing.
With all the systems, I'm coming to realize that a light touch is important. The stones all remove metal at their own optimal rate when I don't try to force the grinding. Forcing things least to poor grinds, mistakes, crappy convexing, and in one case, a BK14 with a noticeably smaller blade.