With cardio titles like Beat Saber, or doing something like swinging a lightsaber/using the Force in Darth Vader's training dojo, it's easy to work up a sweat when using the Quest. Unfortunately, it's equally easy to soak through the foam of the Standard Facial Interface, after which the sweat starts soaking into the hard outer casing of the Quest itself. This has happened too often, and using the Eyeglass Spacer to stop this isn't a solution if the image in the helmet is slightly out of focus no matter how much I jockey the headset (I don't wear glasses).
Ronny Neumann commented
Oculus already has a faux-leather facial interface they are shipping with the business versions of the quest... i don't understand why they don't sell those to the rest of the consumers :(