The long and short of this review is these are cute little guys but they'l turn on you in an instant so just be careful!
Everyone will want something different out of their trip to the monkey forest so decide what you want and go for it. If you interested in getting pictures with the monkeys climbing on you then buy some bananas and carry a water bottle, it will attract them instantly! But just know that these area very smart wild animals so their behavior is unpredictable and they will bite you.
If you don't want them to bother you and just want a few pictures (like I did) just take off all jewelry and sunglasses and keep you hands where they can see them! For the most part they left me alone, but these little rascals are so smart that when I put my hand in my bag to get my camera, they would approach me. I asked my guide why they do that, he said "because they think you're going to pull out food and they want to get to you before the others." See what I mean smart!
In the spirit of planet of the apes please respect that these aren't dumb animals and they will do what's necessary to get what they want from you.
Overall it was a cool experience, more of a check the box activity because everyone said I HAD to go if I was in Ubud. I'm an animal lover and these guys were super cute (especially the babies), but for some reason being there made me uncomfortable, if they decided to revolt we'd be in trouble!!
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC