My recommendation is to start collecting them, and figure out potency later
I have some bridge, some torch, and the Pedro. The potency does vary, as well as the types of alkaloids present. The species of Pedro that I have had produced more dreamy effects, where the bridge produces stimulating effects.
There is a lot of contradictory information about cacti - that's why I decided to find a little bit of each species and see where that leads me.
I'm not knowledgeable about which clones have the most content.
Good luck!
Sometimes it's good for a change. Other times it isn't.