I have them in all 5 colors and I love them!!!!!
I use them almost daily and feel naked when I forget it.
I give them out to friends as presents and they love them. They are always commenting how nice it is to be able to up it on their keys and always have it with them. I have actually gone through TSA screening and no one has ever questioned it.
These are things that everyone needs and should always have on them.
It also goes with rule number 9 from NCIS : Rule 9: Never go anywhere without a knife.