Dock & Port covers?

Has anyone ever used these? I was reading a post where they had never dropped it in water but their sensor in their headphone jack was still red. Of course, now I am terrified this is going to happen to me.

Has anyone used the dock/port covers? Where did you get them? Are they even worth it? Of course I am just talking about protecting from water damage from rain or something when you are out and about, not dropping it in the pool or something

thank you but that other thread was more about where to get them and I can find them easily. I wasn't too clear as I did say where did you get them, but I meant if you like them which ones do you like vs others. Sorry about that. I just don't want to spend money on a product other people think is pretty useless.

I just wanted to hear from people who actually used them and if they found any benefit or if they were just annoying to keep track of.

Thanks!!