I think Monster and Beats put out a line of quality product. Is it for everyone? Probably not, but quality nonetheless.
NOW, the real question that I posted earlier is whether or not they're worth the money.
I don't consider myself an audiophile at all, but I know what sounds good TO ME. When I bought the Beats Solo HD, I admit I bought into the hype, marketing, "It's expensive as hell, must be good" logic, and finally, it does sound good to me. However, if I did a little more research and spent more time looking for headphones, I definitely won't get the Beats Solo HD.
I do have post-purchase remorse with my Beats, not because I think it's a bad product, simply because I think I over-spent. I listened to some $100 Sony headphones, and they sound just as good as my Beats Solo HD. I listened to some similarly priced Bose headphones, and they blew my Beats out of the water. But I'm not about to justify a bad purchase with another purchase.
To the average consumer who aren't audiophiles and know everything about music/sound, the plethora of choices on the market can simply confuse the consumer.
Lastly, I heard stuff from AKG aren't half bad either?