I use japanese water stones. I spent nearly $250 on stones before I learned about the Edge Pro. I wish I would have waited and got that one instead, cause it lets you set the angles exactly where you want, and it's impossible to mess up.
That being said, I don't go for a specific angle, cause I have no easy way of measuring it, but I take the time to go slowly and keep the angle I do have, consistent.
It is kind of relaxing and helps me focus on my thoughts well, while I'm doing it though.