I use an EdgePro for the following reasons.
Sharpening is all about selecting an edge angle and then being able to sharpen, and importantly….re sharpen, at that exact same angle, so one not only finishes up with a sharp edge but also an edge that has even bevels, both sides, and looks darn good.
The angle setting device should be infinitely variable and 100% repeatable so that all knives can be sharpened with the minimum of metal removal.
Grit size needs to be quickly changed for re profiling and varying degrees of sharpness. Some of my knives have mirror polished edges, arrived at with 6,000 and up grit.
Other blades, mostly used in the kitchen and requiring a little 'tooth' , get the 220 grit treatment. And sometimes I will use a combination of both, all on the same blade ( who needs serrations ).
The only sharpener system I know of that can do all this,
is the EdgePro. A truly remarkable sharpening system that will save you money as you won't buy anything else afterwards.
Now a comment on the Sharpmaker 204.
The 204 does an excellent job on knives that match its angles, but it fails to be seriously considered as a 'full sharpening system'. For this, one should look for something with infinite variable angle adjustment at the very least.
The Sharpmaker is primarily a 'touch up' tool, that only works on two fixed angles, 15° and 20°.
If your edge is not at one of these two angles, you are forced to hold the blade tilted from vertical ( guess ), or re profile to 15° or 20°. Re profiling is not best suited to 'V' rod/triangle style sharpeners as it is very time consuming and really needs the expensive diamond rods to accomplish this. If you purchase these you are now up in price to the EdgePro Apex.
Also with the Sharpmaker, you must not let the blade run off the end of the rod during the sharpening stroke. If you do this more than a few times, you will round over the blade tip. Not desirable.