Hello. This is one of the first things that I did when I got my car. Initally I made my own from the ipad screen guard as you said, but then found that a company acutally makes pre cut ones. My car is a mk 7 though, so I know that your infotainment screen is different, but if you search amazon, they may have brought out ones specific for it as well.
With regards to operation, I acutally went for the gloss ones as opposed to the matt finish. It works very well and I like the finish on it as well. It has no impact on operation, so win win all round!