Depends. If you wanna fit in with the cool kids, you need a macbook. If you want functionality get something else!
Can you really justify spending about a £1000, on a flashy computer? Or would it be better to spend less and get a chromebook or decent laptop?
Macbooks are great for Photoshop etc, but if youre not doing graphics/art/photography then theres not much need. It will also cost more than what you've forecasted because you'd be crazy to splash out about a grand and not get insurance on it! (which will be a further £200 or so).
On the other hand, they do run really well, are quite reliable and are easy and quick to use. Plus they cant get viruses (but neither can chromebooks - just sayin!) like a laptop would.
I'd get a cheap but decent laptop, and stash away the rest of the money for a holiday or something.
Regardless go to PCworld/Curries etc and play on all the computers, there should be one that you instantly like (from use, not aesthetics!) and thats the one you should go for. If its a mac, then so be it. (also check out the second hand ones, might save you a few bob!)