I passed through Heathrow on my way to a deployment with the Army 4 years ago. Not sure if it was the place your talking about but the Duty free shop we shopped in there had cc's. The prices were so inflated compared to the cc's we bought from the locals where we were stationed. Once we learned how much more we paid we didn't even try to shop at the airport on the way home.
One suggestion I can offer is price out the cigars and use this comparison. On average I've bought them for 8 to 9 dollars a stick from the local cigar stores wherever I've been stationed. I'm willing to pay at most two dollars more than that if they look in good condition. Other than that it just isn't worth it to me.
Hope that helps put it into perspective for you.
