Brian Holcombe
Thanks David!

I do always see stray scratches with natural stones, but unlike synthetics they never seem to result in fractures beginning where they end.

This one continues to linger in my mind;

http://www2.odn.ne.jp/mandaraya/pkuwaido-maikurosuko-pu.html

At the bottom of the page there is a 10x that might be the best of both worlds, I'm sure its pretty high quality and not as expensive as the 150x.