Love my Maui's
Some of the reasons I like the more expensive Maui Volcano's (wish there weren't so much of course):
The spring loaded hinges
The dual shaded lenses (brown top and bottom, grey in the middle)
The glare shades built-in as part of the frame's shape
I don't know if there are shades of polarization, but I find this to reduce glare extremely well.
Wish they were just a TAD darker on those very bright days and lighter on cloudy ones, or when fishing under trees on a stream.