They only sell to people leaving the UK, just an FYI of anyone thinking of booking a cheap domestic to pick one up.

Also worth having a conversation with the staff, a desirable bottle (one which sells for greater than retail price) I enquired about was out of stock once, but after speaking with the sales guy for 5 minutes or so about whisky and my collection, he remembered they did in fact of one in stock in the back...

So just enquiring if they have stock, you might be told no, but that doesn't always mean they don't have stock.