indicas have high cbd and cbn levels so that gives em extra medicinal points. And i honestly believe that no plant is more productive in potency than the other. Their canabinoid levels are just different. Sativas have lower levels of cbd and cbn and usually go high in thc, giving a total different high. I must say again its not easy to grow a sativa. If the grower is experienced enough to keep the metabolism of the plant in right levels so the plant doesnt abuse food but just takes what it needs, you can have incredible results. Ive seen ENORMOUS colas in some outdoor sativas, dripping with resin. A guy i knew used to harvest more than a kilo of incredibly dank bud from each of his 3-meter-tall monsters. But i have also seen badly grown sativas with spindly buds and burnt leaves fighting to stay alive due to fert abuse. So i believe is up to the grower to grow a helthy dank sativa. Which is not very easy and needs experience.