I use either the mendo mulcher or the orange plastic grinder that comes with the volcano, which is surpringly efficient. I don't grind as fine for the solo as for the mflb. I look for more of a fluffy grind to expose maximum surface area to the warm air passing through. Results for me are consistently very good this way. Evenly toasted throughout without the need to stir during a session. The santa cruz crusher seems like a good grinder also.