Have never tried Silene Capensis, but will vouch for Calea Z.

Also, I don't find it to be a harsh smoke, and the smell is fantastic.

The only thing to note is

1) Make a strong tea and brew it down to a shot glass'es worth so you can drink it all in a onner.

2) Cuttings are more difficult to take than something like salvia.

   So, use a hormone rooting gel (clonex) and keep the young plants (up to 2 months old) in a humidity tent / jar / plastic bag;

even long after they have rooted and been potted, otherwise they will just dry up and you'll be back to square one. Once the plants

are bigger, they can survive without the humidity tent.