If you want sharp, you have lots of options. If you want measurable exact flat angles, no freehand method I have seen, can do a museum grade presentation. For that you need a jig, and time.
The last item in my signature area, is what I would call a great overall sharpener. Fast, accurate, repeatable results. It does not do exact anal flat edges. It does do sharp sharp sharp fast fast fast. It is hands down, the best slow (no / low heat) belt system I have seen. Being a belt, it is fast. Having a built in jig, it is accurate, and gives repeatable results.
I would score the WorkSharp Ken Onion edition, almost a perfect 10. I lower the score only slightly, as one side cuts into the blade, while the other cuts away from the blade. I also am a fan of perfectly flat bevels, and the WS KO does a convex edge. It also will not do some blades with thumb assist openers. It does not do well on KRIS blades (but a narrower belt might make that work).