Most goggles have polycarbonate lenses, so pricey ones will scratch in about the same way as cheap ones, which is easily. When they aren't on your face, keep them in a pouch or goggle pocket, and only use an appropiate cloth to clean them. No wiping them off on your sweater! Some expensive brands (like Oakley) may claim that their lenses are tougher. This is complete bullshit.
Anti-fog remedies usually work in two ways: ventilation or coating the lens with a treatment. You can buy the lens treatment in any ski shop, but you are stuck with the ventilation that your goggles come with. Look for models that have lots of ways for air to circulate, but that will also slide shut in super windy or cold conditions.
I like Smith goggles. Not only do they make the best lenses for flat light, they are optically precise and they have a lifetime warranty. I've broken hinges on their glasses before and they sent me a whole new pair. It's a good company, and slightly less expensive than Oakley. Here is a cheap pair.