The Japanese site dvd-r.jpn.org has added a test of various "scratch-proof" DVD's to it's ongoing sunlight test.
They pulled each disc over sandpaper with increasing weights added and rescanned each time with PxScan on a Plextor PX-755A or 760A. Results are up for about 1/2 of the planned 13 media types.
They use a neat display style that lets you click through the results like a flip chart.
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