We just traveled from Miami to Glasgow via LHR. And as Techno123 suggests, there is indeed a mountain of luggage which did not make the connections chosen. We chose to ship our luggage in advance to Glasgow (and it was in our hotel room when we arrived). Some others in our tour group lost their luggage in LHR. My suggestion is avoid LHR if you can or ship your luggage in advance. Luggage Free is the carrier we chose.