So I would use the beats for the Ipod touch, Xbox 360 and 3ds, are they worth £150-£200?

Worth it? It depends. If you truly enjoy an amazing audio experience, yes they are worth it. If you are really capable of keeping things undamaged and baby your electronics, it's worth it. I'd say for the uses you are using it for, it's not necessary, but might add some extra gaming quality. You'll like it for iPod and Xbox, but the 3DS doesn't put out the greatest range for sound quality, so it's not going to make a huge difference on that.

Do you have them?????

Simple answer: No

There are better products with better prices.

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You can recylce a book and turn it into a paper plate, But it always is and will be, a book.

They are good, but very overpriced....

I want to know if a pack of Klenex used by Dr Dre is worth it.

Nope, not worth it. You can get headphones that are just as good from companies like Sennheiser for less. If you aren't an audiophile, I wouldn't bother. If you are, by all means go ahead, but I'd recommend Sennheiser over beats. Too much hype for the Beats.
I can judge because I've had both*

Get the Justin Bieber ones instead!~~~~
No, don't. Get Skullcandy ones. They're fab.

yeah they are expensive, but truthfully, nothing out there can match them. for the audio experience that they give you, they're actually pretty fairly priced.

Yes I have used them. I don't own a pair currently, but I do want them. I will look into Sennheiser a little more, cuz when I was looking, I didn't find anything that sounded quite like them. Plus they are pimpin and Dre is coming back, so... yeah.

^^ This. He gets it. It's the same as do I buy a Philips mp3 player or just go buy an iPod. There is a difference although they do the same thing.