I for one am going to keep flying to LGW if London is my final destination. LHR just has too many delays and too much congestion. I have only flown into LHR a handful of times (when I could not fly into LGW) and every time we were either waiting 30 minutes before we could land (doing the circle dance) or waiting on the runway FOREVER to take off. Gatwick is a breeze and I use Gatwick express to get downtown.
I can understand if you are using LHR to connect onward to other cities ok, I understand that. But for me personally if I am terminating in London it's LGW for me.
If I had to connect in the EU I think I would rather use FRA than LHR. LHR just has too much congestion. And the security lines at that airport. Good grief.
I know some of you have said on here you're losing half a day once you land in LHR. You will be lucky if your hotel room is ready for you most of the time once you land that early in the afternoon. Unless you are going straight to your business meeting before going to your hotel.