I dunno....
£50 would be just enough to buy a decent 500W PSU... let alone a decent case together with a decent 500W PSU... and since that case is a special "designers/modding" case I personally would not buy that as I think the PSU must be a very cheap one for that price.
I-Cute 0408XL-BS
The prices I've seen for that case alone, range from £30 to £60... let alone that you can have a decent 500W PSU for the rest of the money...
I wonder what you're going to do with 500W anyways though