It's first and foremost a warm fleece hat with a shape that comfortably covers your ears and the back of your head without getting in your eyes. The pull-down facemask is more compact and convenient than a scarf, but not as protective or breathable as a real balaclava.
Pros: compact and light enough to carry in all seasons; warm enough for most winter uses. The facemask does help when extra warmth is wanted.
Cons: Not entirely windproof. Does not fit comfortably under a helmet. Facemask not breathable: causes fogging of goggles unless pulled down to neck.
This is my go-to, 90% solution hat. I also carry a balaclava for serious winter winds and for situations where I need to wear a helmet in the cold, but this hat is what I reach for most of the time when I need a hat, year round, in spite of it having been called 'the dork hat' by someone who was dating the dork.