Re scratches-- I look after mine with Pledge and CLEAN microfiber cloths, and in our dusty environment I can get about a year or a bit more out of it before it starts looking tatty. I think you have to consider your riding environment depending on how dusty, rocky, and what the road conditions are like.

I consider any shield to be a consumable item and I'm happy to replace it yearly if needed. LRS shields are reasonably priced so no probs there.

BTW I have a 10" X Stream on the 09 BargeGlide and I look over the top of it by an inch or so. I'm 5'10" on a good day...

 

For what its worth, I have a friend who is an avid drag racer and he has lexan windshields. He says he cleans them with aim toothpaste and it prevents scratches and even helps remove them.

 

I've got one of the 10" flip's in dark smoke and I love it, works better than the taller windshield I had with no filp in it.

 

I would go with the Clearview re-curve.