In almost 7 years I haven't seen any negative effects from using it, it's extremely slim and it's supposedly made from a special fabric. Just make sure you keep it clean and free from any thing that could scratch the display and you should be fine.
I highly recommend it.
The AR coating issue cannot be prevented as its a defect where the coating starts to basically break down without even touching it. It starts usually from the bezel and the keys cannot be blamed ever for this issue.