stayed at this lodge for 3 nights. great experience walking through the amazon rainforest and getting a chance to see many many insects. my guide was Oscar who did a really good job making my group & i feel as comfortable as possible. Oscar also answered all our questions about nature/insects. Food provided was well done too. Only negative point is that it gets dark early and with little/almost no electricity, bugs were annoying me during dinners and it can get quite tough to see at night, so bring a flash light for sure! and be prepared to take cold showers - hot water is said to be provided (and some rooms did enjoy this), but my room didn't have any.

I'm a little late in writing this review.

We stayed at the Posada Oct 8th through Oct 11th. The lodge grounds are pretty and well kept, the rooms are clean and comfortable and the staff couldn't be more helpful and accommodating.

I wasn't sure what to expect when I booked this trip, but I knew that I didn't want a group Disney-like tour. So, we opted for a private tour guide, which made all the difference. Our guide Fernando managed to show us 7 species of monkeys, so many birds and parrots that I lost track, giant river otters and more. He taught me more in 4 days than I've learned in the last 5 years of traveling. My mom traveled with me and she has a bad knee which makes climbing stairs difficult. He was patient and kind and made sure she was comfortable on the long hikes. The guides eat breakfast, lunch and dinner with you so you really get to know them. Fernando is truly one of the best guides that I've ever had on a trip. So much so that I'm planning my return in Oct 2012.

A couple of details and tips you should be aware of -

1.) Hire a private guide - it's worth the extra 80-100 bucks. You will see much more and you will learn a lot!
2.) The food is good, but it's local so if you don't like rice and beans then you might have a problem.
3.) The lodge has hot water, but it may run warm at peak times. We ran out of hot water once during our stay, but otherwise it worked just fine.
4.) Because you're in jungle you only have electricity in the morning, a hour or so in the afternoon and in the evening.
5.) To get to the lodge, you drive about 45 -50 minutes down a dirt road and then you transfer to a dug out canoe which goes about 45 minutes upriver. Then you have to climb up a lot of stairs and hike about 10-15 minutes. It's hot, so be prepared to get sweaty. Upon arrival at the lodge they will give cold towels and then you're given a 30 minute introduction by Cesar, the manager.
6.) We had no problem with bugs, but take spray and sunscreen, a flashlight and extra battery pack for the camera as well as poncho.
7.) TAKE local currency. Peru has some weird thing that if your money is worn, torn or creased they won't take it b/c the banks won't exchange it.
8.) The lodge seems to host a lot of travel agents who can be noisy. Thankfully on our stay they only stayed one night and then they were gone.
9.) 3 nights is plenty of time in my opinion.
10.) The tours start very early and then afternoon is usually spent at your leisure. If you have teenagers this downtime may be a problem. I waiver on whether this lodge is appropriate for kids. Tours resume in the late afternoon.
11.) Our room was one of the last rooms in the far back against the jungle. I think it was #12. In any event, any room on this wing is good for wildlife viewing. We had a few monkeys come visit at night and during the day we could lay in our hammock and watch them jump from limb to limb.
12.) Try to remember that the jungle is much different then a safari. Some days the viewing will be intense and others you might not see anything.

In summary, I HIGHLY recommend the Posada for anyone looking for a soft adventure or intro into the jungle. Also, the story behind the Posada and their sister lodges is a wonderful and inspirational story.

We did the 3day 2 night one and were pretty happy with the experience. The room & shower opening out to the jungle was a nice touch. The guided hikes, macaw-watching, fishing trips made it a memorable one. The one thing I will never forget is the continuous sweating due to humidity!!

The food (especially for vegetarians) wasnt great (but not bad either) and we had some water problems couple of times.

Most of the other reviews I read were accurate in describing the facilities, so I won't repeat that. I traveled with my wife and 22-year-old daughter, and our stay was the high point of our two weeks in Peru.
Our guide, Luis, had phenomenal knowledge of the jungle and helped us to appreciate (and see) a variety of wildlife -- highlight was getting underneath and following a large group of monkeys moving through the jungle. The food, lodging and staff all exceeded expectations -- very nice people. We do a fair amount of hiking and camping , so perhaps we were more comfortable with the facilities, activities than some other reviewers. But I think that if you read up about eco-lodges and read Posada Amazonas' own website (recommendations for gear, clothing etc.), you will be well-prepared. This is not by any means a spartan, harsh experience.
Also, the cultural experiences involving the native community, such as visiting the shaman and taking the natural medicine walking tour, and visiting a nearby farm, were much more interesting than I expected.
One caveat -- we arrived in one of the occasional cold spells, so the temperatures were uncharacteristically moderate to cool, with virtually no mosquitos.
I would recommend doing the four-day package and savoring the difference from your normal world -- that's the point.