I have only used the old Sharpmaker, anyway :
The current Sharpmaker has two preset angles and two grits. The Edge Pro Apex has a smooth angle adjustement covering a range of angles below and above the Sharpmaker (roughly 10 to 35 degrees). The Apex also has a range of 5 hones + 2 polishing tapes (you get two hones with the Apex, the others are add on's).
The Sharpmaker is quicker to set up, and the ceramic rods do not have to be lapped unlike the Apex waterstones. The ceramic rods clean easily with Ajax (or whatever) and a scrubbing pad. The waterstones can load and then need to be lapped.
The Apex will recut a bevel (change the angle) *much* faster than the Sharpmaker. This is not a small difference, the time is shortened by a factor of ten or so and is one of the major differences.
You can use an x-coarse hone in conjunction with the Sharpmaker to do the reprofiling which will speed up the process significantly. I think Joe Talmadge was the first to suggest this.
The Sharpmaker is easier (faster) to use on a blade that is just a little under sharp. You pop it together and give the blade a couple of strokes. Of course you could simply leave the Apex set up at some fixed angle with the x-fine hone and it would be as fast. But using just one angle and one hone is a severe waste of its abilities.
-Cliff
