I just wish I'd seen GMYLE keyboard covers before I bought the crappy inferior cover for my Macbook on eBay. It's like drumming a tractor tyre with your fingertips.
Thankfully I have this one on my Macbook Air, and it's great - clear, so it doesn't obscure the keyboard backlights, and virtually unnoticeable when you're typing. And it's a lot thinner than the eBay crap.
More importantly, I'm reassured the damage will be minimised when the inevitable happens, and I foolishly get my computer out to look up a funny cat video on YouTube, and some plonker spills a pint of beer over the keyboard one evening when we "thought we weren't that drunk".