Do you think it is necessary to fit mirror protectors to a PVC? If so, which ones? Milenco at around £60, or Van Comfort or Mirror Guard at about twice that? By my reckoning a new mirror would cost around £300, and expensive mirror protectors around £130, so it's only greater than a 1 in 2(ish) chance of my mirror being destroyed that makes this purchase financially viable. Did I get that right? Says nothing about the inconvenience of a broken mirror though.