1. Lenses not polarized.  This is a GOOD thing.  Polarized lenses are excellent if all you do is look at water or sky directly (or any other high-glare situation).  Polarized lenses SUCK if you have to look at or through other polarized glass.  Mobile phone glass?  Polarized.  High-end visors on motorcycle helmets?  Polarized.  Flight displays?  Polarized.  Cockpit windscreens?  Polarized.  That circular polarizer protecting your expensive camera lens?  Yeah, of course, polarized.

Looking through TWO layers of polarized glass (sunglasses + whatever else you're looking at or through) is horrible.  The image will be both dimmed and distorted.  Trust me, you don't want polarized sunglasses unless you're damn sure nothing else in your day-to-day world isn't also polarized.

2. Bayonet temples rock, if you have to "work" in your sunglasses.  They aren't a huge advantage for most folks, but if you have to put on / take off sunglasses while wearing a headset or a helmet, they're the only way to go.

I recently lost my pair of navy-issue sunglasses given to me as a gift 20 years ago by a friend who worked ATC at Alameda Naval Air Station.  I didn't realize how fine these glasses were until I tried to replace them (going through about a half-dozen different high end offerings from "big name" manufacturers).

In 5000+ hours of flying professionally; I haven't found a better set of sunglasses than these.