I've had two Drill Doctors. The original boxy one worked without problems. The later, low profile 750X seems to be a bit technique sensitive, but works just fine. My problem with it was getting a positive rake from time to time (and all the problems that caused). But, Drill Doc gives you a like-new resharpening job and I used those drills for years on various mills.
I switched to four-facet sharpening a year ago. There are a bunch of sharpeners that can do that, mostly shop made (search it), but if one understands the geometry pretty much any surface grinder and a simple fixture will do it. The result is an end-mill like cutting edge on the drill, rather than the standard relief pattern seen from the Drill Doctor. A bit of a pain to get everything switched over, but worth doing. The decreased cutting pressure (and less wandering) is the result of a pyramidal point, rather than the standard chisel that pushes material away. I've never measured cutting force, but drills using a four facet grind do seem to feed more easily by hand, for what that's worth.