It's really expensive but a little goes a long way; it works wonders: my under eye circles went lighter right after applying this and some days later it even looks shiny and plumper.
This is my only MAC brush but I really like it, it does buff eye shadows the way I like without "harming" my eyes (they're very sensitive, so I can't use any brush); the only con is that is a bit pric...
It's a very nice moisturiser but it's really expensive; especially when you're a student on a low budget.