Pros: Decent sound
Cons: They will try and eat your head
I bought these on a whim and a good vibe that they'd be my best headphones ever, and they're not bad. It's just that coming from better headphones and good IEMs, they don't particularly impress. Half the stuff at this price point sounds as good as these, and some of those are more comfortable and closed back. What you're getting for your 40 or so bucks is some very cheaply made headphones that will grab your hair and press on you ears and head in unusual places. The foam will also disintegrate in a few years; it will literally fall apart, but at least getting replacements from eBay is extremely cheap and easy.
These things do include a lifetime warranty, but you may find that it's easier to buy more than to mess with shipping and getting them returned.
In their favour they do impress me each time I use them, but invariably the little hook used for clipping the headband to itself will start to gnaw my ear, or I'll adjust them and cause the spring loaded comfort setting to alter, which has to be set each and every time you put them on anyway. Then after a few hours use over a couple of days they get forgotten again.
They do look cool, and everybody here should own a pair, but I do get a little tired with how much they're vaunted.