Yes, it is very weird! I now generally consider that if they are stretched out all the time, then they need replacing. They should just be below the limit when the camera is just hanging there. The worst bit is when you have to do a compass calibration, spinning the drone over itself ends up stretching out all the dampers a lot - that's probably what does the damage.
They will leak if squeezed too hard; you need to be extra careful whilst fitting them, which never seems to get any easier. (I use the blunt, rounded end of a paint brush for that.)
The new H520E uses more of the dampers, presumably because of this.
Yuneec just aren't very good at doing the minor upgrades and design improvements that all products need. The camera tilt switch on the ST16 controllers (top left) is, still a 3-way switch when it should be a 2-way! Any normal manufacturer would have changed that when renewing their stock! Makes you wonder how the company is run.
Wow. Thanks for posting those replies. Whisperit and johnnyb57, I ordered rubber dampers for the e90 and they look identical in size, but I swear they're impossible to get on. I'm gonna try the rubber bands. They look perfect. Just got to find those same ones.
I was also wondering about filters. I ordered a hoya