I had one of these last year. I'm guessing you might be in Cambridge, because I know one of the colleges was selling several bottles of this off particularly cheaply. (I got six bottles for £16 each, which I thought was a bit of a bargain!)
It was absolutely gorgeous. Instructions as to above re decanting etc are all v. good. But do save it for a special occasion, and make sure the people you share it with will appreciate it!