It is easier to go with the current. Most lodges are located downstream, and closer to Iquitos, having less chance of observing animals in their natural habitat.
There are two types of passengers. There are those who are looking for: more comfort such as swimming pool, A/C, with traditional activities such as visiting tribes, observing and touching animals at a close distance. And, others are looking for: authenticity in the excursions, animals in their natural habitat far from civilization, with low environmental impact working with the community, combined with adequate comfort.
Comfort and authenticity are possible within the Muyuna experience.