I wear the nude shade so often, I'm already on my second one. I also have the Fuchsia colour which I purchased specifically for the MAC All Fired Up lippy.

Pros:
Love the staying power and the colours are so beautiful.
The retractable pen is brilliant, no searching high and low for a sharpener.
The liner doesn't fade easily and doesn't dry out my lips
Can be worn as a lipstick
One liner can last you for a few months
Cute packaging (The actual pencil is nifty, doesn't mess and the long top stays put)

Cons:
It's really pricey for a lip pencil but you're definitely paying for quality