The factory edge on SAK blades is 30 degrees. I saw this in a video of the factory process. It is done with a laser, by the way.
I always leave the pen blade at 30 degrees and hone it to razor sharp with my fine white Sharpmaker stones. This is perfect for whittling.
For the main blade, I hone it to razor sharp at 30 degrees, but afterward I finish the edge at 40 degrees, to create a micro-bevel. I do this because I use the main blade for utility type cutting, and a straight 30 degree edge dulls too fast when used this way.
I always finish with a leather strop with some diamond spray.
By doing this, I can get my blades razor sharp, requiring only a few strokes on the strop or Sharpmaker to keep them that way.