The best goggles are ones that fit properly and are comfortable to wear. Ensure you get the right size for your face and, if you wear glasses, choose a pair that fit nicely over the top. The foam is vital for comfort, but also necessary for keeping the dust out, so make sure you have strong, high-quality foam. Lens quality is also important, and scratch resistance is an absolute must. You may want to also consider UV protection, anti-fogging, or different tints.