Danish Army: Earlier on we got issued Wiley X, then Revision and I hear we are getting new test versions again next year.
I wear my Ray-Ban Aviators at drill all the time.
"Official Army Issue" doesn't really mean anything anymore. Nowadays individual units' supply sergeants are given leeway to use company funds to go shopping for whatever their soldiers may need. For a deployment to Iraq I once got "issued" elbow and knee pads for skateboarding that were purchased at Toys R Us (ESPN "X Games" brand).
While they're given a bit of wiggle room on what they can order, you can't go buy whatever you want. There are approved lists for uniforms, eyewear, foot wear, underwear, gloves, etc. I know that if were were caught wearing anything other than that wasn't on one of the lists, we could get in trouble.
In the '90's we were just issued dust goggles. In Afghanistan in 2006 or so I started to wear Native sunglasses, after I met an ODA Captain who'd taken a 60mm mortar round IED in the face at about 5 meters while wearing them. His face and sunglasses were sandblasted, but his eyes were fine. I was a contractor, so everything for me was a private purchase.
Whatever, I had sæx last night in a cornfield wearing my Ray Ban. I win!
Topic: During my basic i bought a pair of Revision eyewear with prescription, they were pretty good and probably saved my left eye, when a hot as hell cartridge, were ejected from the guy next to me's weapon.