I think it really depends on where you drive and how you plan to use your defender. I am a huge supporter of the can am glass flip out windshield. I drive mostly on roads, but there is that occasional trail ride through the woods and mud so I am really grateful I have the ability to wipe off mud or take brush to the windshield without scratching it. Even trailering it in not so ideal conditions I can get to my destination and wipe it off without worry of scratching it. It is a little pricey on the front end, but I think it is more than worth it. just my opinion.
My only regret was not getting the wiper installed right away.