I bought some anti-glare, scratch resistant film which is way better than the original protection plastics for 10. Makes usability also better than without, as the finger really glides now. They're also reusable, meaning that you can take them off and wash gently with soap, then re-apply. Protects both back and frontside (altho backside doesn't matter to me since I made it "brushed" already). Adds no extra weight or size, 1-year guarantee.
I also forgot what it's are called.