The greenstar has a few pieces to clean up, but once you get used to it it's not so bad. Some others may be a little quicker, but they are not supposed to retain the nutrients like the greenstar.

I also plan to sauna soon. We bought a used heavenly heat sauna last year, and I am still yet to put it together. My dentist told me that saunas on a regular basis can pull a lot of the mercury out.