I'm new to wearing makeup daily and heard great things about this product through friends and watching a lot of online makeup tutorials. I love the colour of this product (I chose Blackest Black), it's very intense and looks great. I've also owned the Charcoal colour for some time and did find that it smudged -- HOWEVER, I was reading online to prime the eye before using products on it, which I did with the Blackest Black, and I had no smudges whatsoever.
The only reason I am giving this product a 4/5 is because I don't care for the brush it comes with. It makes the line rather thick, and I prefer to build my line up then be immediately stuck with a bold one. For any newbies out there, I'd recommend getting the Mac 263 brush, or any small angled brush to use with this product, especially if you prefer thinner lines or building the line yourself :)