I've been travelling between Lagos and Heathrow for the past 10 years.
When I first started, Lagos was indeed a nightmare to pass through, with corrupt immigration and customs officials.
On my last trip a few weeks ago, I was off the aircraft, through immigration within 20 minutes (even from the back of the aircraft), and I had my case in my hand 10 minutes after that, despite the baggage trolly being powered by local staff pulling it from the aircraft to the arrivals area.
My last arrival at heathrow was through T2.
A queue of what must have been 200 people with EU passports, all trying to get through 2 immigration desks, whilst there were at least 20 desks for non EU passport holders.
Then a 30 minute wait for the bags to start arriving.
Heathrow is a national disgrace, but how it came out worse than CDG is beyond me.