Yes I do and I purchase generic covers I am not into paying more because it is a "special brand".
Having said that I like to choose ones with lovely artwork so my current one has a lovely painting of buddha on it.
I have a protective film on the front of my phone and a clear plastic cover on the back which is a cheap cover purchased on E-bay because I like the burgandy case of my phone and didn't want to hide it. A couple of days ago the battery died so took it out of its case and asked the sales girl if she would replace the battery for me. She looked at the phone and commented that it looked brand new. I smiled and said that was because it has been encased in a cover since brand new.
I have a white leather (flip over) 1 which also holds my 2 travel cards for Sydney & Melbourne. As I only use it to tell the time, it's ok for me to have a flip over 1, as I don't have much in my handbag, the slight bulkiness of it, doesn't worry me.