For my ZT's in Elmax, I sharpen them to a bit less than 20 degrees per side, and I'll maintain the edge on the Sharpmaker in the 20 DPS position. Effectively, I end up with a secondary bevel that's a little more acute than 40 degrees inclusive and a 40 degree microbevel. That's been a good balance between sharpness and edge strength, at least for my uses.