I have three systems that I use heavily: EdgePro, Sharpmaker, and a Kalamazoo belt grinder.
The EdgePro is my go-to for when I have a knife that I need to be absolutely PERFECT, like someone's grandpa's WWII KaBar. I work through the factory stones (except the stock 120, that stone is crap, and replaced in my rotation with a DMT XC plate) then down to a Chosera 5K, and a Chosera 8K Snow White. By the time the series is complete, the bevel is literally mirror polished. I let the slurry build up on the 8K a bit for a finer finish. I could add a 10K and a 15K to the rotation as well if I wanted to, for even more polish. Those edges are paper-shaving, hair-popping, tomato-lacerating sharp! Holding the knife on the table is an exercise with a bit of a learning curve, but it's not a long curve. FFGs are about the easiest to do, I think, because there is no confusion over what plane is your reference as you move the blade across the table. Give it ten or fifteen knives, and you won't even notice any more, it just becomes second-nature keeping it flat and moving. Also, the drill-collar trick makes adjusting for stone thickness a matter of seconds. I would certainly buy mine again, it was pricey, but worth every penny. Aftermarket stones improve it yet more.
The Kalamazoo is unbeatable for anything involving more than one knife per hour. Just this last weekend I went on a fishing trip with a friend and their extended family, I must have done 30 knives on my Kali over the course of a day, ranging from fillet knives to to folding and fixed-blade fishing knives. The state of some of them when I started was truly appalling, most of them had either been totally neglected or yanked through one of those carbide "sharpeners" many times. One was even missing a quarter-inch of point where the guy tried to stab it into the cleaning table and botched it. My rotation ran 120 grit (if needed, like re-profiling that point) to 220, 400, 15u, 9u, then green on leather and white on leather. Only one knife out of that 30 or so would not cleanly shave hair when it came off the belt, and that one looked like it had been worked on a grinder at some point. I suspect it was cooked before I got it, the sparks off the 220 just didn't look right at all.
The Sharpmaker, oddly enough, is about the single most-used tool I have for my personal knives. All of my EDC stuff is sharpened up through 8K on the EdgePro for V-bevels, and 30K on the Kaly for convex, so all primary metal-removal was done long ago. As soon as any of them (even the convex) start feeling like they're not quite as 'grippy' as they were to begin with, three or four very light passes per side on the Sharpmaker fine rods will get that edge right back where it belongs. I've tried it for primary sharpening, and it just takes WAY too long to remove any amount of metal. If you need to sharpen any number of knives that are in BAD shape or have damage, you'll want something else. If your knives are already in good shape and you're looking for something to KEEP them that way? You'd be hard pressed to find anything better and more convenient, I think. Something I'd love to see would be a couple of hardened-steel rods for it, so you could literally use it as a bench steel.
I haven't had a chance to try a WEPS yet, but I've got to say it looks good!