Really stressful! The way the camera moves and the sound of the music / ambience gives a real sense of actually being there, especially the camera swinging around when the rope swings.
The UI / instructions were a bit confusing. E.g. at first I couldn't figure out how to move forward; I had to watch the video to see that the game wanted me to angle to the right and left before I was allowed to go onward. Also, the curved line seems to be the area in which I need to keep my little marker, but there were quite a few moments where the character's animations didn't seem to match where I was on the curved line; e.g. I tried to keep the marker in the middle of the curve, but sometimes it felt like that wasn't the best action to take. I.e. A bit unclear where I wanted my marker for the best result. I also wasn't entirely sure what caused the curved line to become shorter. It seemed correlated to my walking speed, but not always.
Basically, a few instructions might have been helpful here. But overall, the game feels very raw and real, and the balancing feels very natural (the way you can get into a swing from right to left in an attempt to balance, for example) and just generally fantastic. And yet, it's still easier than it would be in real life!