The problem with goggles is that some fog up way too easily.  The Bobster GXR goggles don't fog up easily, but they do allow a bit too much air to reach your eyes.  Overall, these are pretty good goggles in spite of the amount of air that reaches the eyes.  You can remove the back strap and wear as normal sunglasses.

These would be perfect if:

They were more flexible so that I could make them sit tightly against my face.

Had a few less vents for air flow.