No mirror goggles are actually the best choice if you primarily ski in low light, overcast conditions, or at night. Without that reflective coating, the lens lets in maximum light, which helps you see terrain details and shadows when visibility is already tough. Mirror coatings bounce light away, so they can make dark conditions even harder to read.
The tradeoff is that your eyes will be visible from outside the lens, and you won't get any extra glare reduction beyond what the base tint provides. For sunny days, that missing glare protection can be noticeable. But for storm skiing, tree runs on gray days, or night sessions under the lights, no mirror is the way to go.
One practical bonus: without a mirror coating, the lens is generally more forgiving with cleaning and less prone to showing scratches. If you're on a budget or tend to be rough on your gear, no mirror goggles are a durable, functional choice for anything except bright sun.