If you're in the UK (or anywhere I suppose) you can get Altec Lansing 'Muzx Extra' for £7.99 straight from Amazon, when they're usually supposed to be "49.99" Whether they're really £50 everywhere I don't know- but £8 is how much they're going for on eBay!
Are you sure they aren't used or returned goods? You might want to read the product listing carefully. It's also possible they are an older model that have since been replaced with newer models. Shure did this with their earbuds a number of times. They would come out with a new set of models, and their previous ones would become much cheaper (like $100 less, when they originally sold for like $250-$550 a pair).
I usually don't trust this type of thing. Usually because of the fact that you might get a cheap knockoff instead of a durable and well looking version of the product. I would not recommend buying it personally.
