I have a suitcase full of high end stones as well as the work sharp (with the 18"belt addon), an edge pro, and a bunch of other related sharpening stuff. I use the stones really only for hand plane irons and chisels and a couple of angular tantos (work sharp has a tendency to round if you want straight, at least in MY hands, I haven't tried again now I'm better at using it though)
I really love the worksharp and belt sharpening in general now. It cuts too fast and can damage a blade? Only if you're using too low of a grit. I never go below 220, and only 220 or 320 briefly, carefully and with a light touch (because yes, it's spinning faster than my hand would. speed IS variable though)
Advantage? I need to do movement on only one plane. There are jigs for straight edges (wharncliffe, planes, chisels) but nothing really useful for curved knife blades. The edge pro is much better as far as repeated action, but I can still get a dozen quality knives to hair popping with 2 or 3 belts, including the linen strop with green on it, in less time than 2 knifes on the edge pro.
There's definitely a learning curve for either freehand or work sharp, neither do the work for you, but it certainly helps a lot. Sort of like an impact driver vs a screwdriver. The impact driver has a higher chance of eating apart the head or breaking that screw, but their sales certainly aren't suffering over screwdrivers.
Really, when I first started really caring about sharpening and having quality steels, I could get about as sharp as I can now, but it was a lot more work and took a lot more time.
When I sharpen something with the WS I always end up stropping almost Everything, as well as any knives friends need sharpened.
I really need to put it back away so I can finish up the new chisels though!