The Ultra Crystal is about as good as you can get. It will have the absolute least effect on the display quality. All anti-fingerprint/glare screen protectors will diminish the display quality more than the clear ones to a varying degree. It is a trade off, clarity vs fingerprints. The Flex HD is similar to the Zagg type, but people have said it has less orange peel affect. If you want the absolute least negative effect on your display, get a clear one. If your priority is no fingerprints, and you don't mind a little more loss of display clarity, get the anti-fingerprint one. Personally, I don't like the Zagg type protectors. They have way too much of a negative effect on the display. I saw an HTC One X with and without the Zagg, and wow it really made that beautiful display look like crap.