I live in Manchester so I fly in all the time, I find Immigration to be super quick! We usually get through in minutes, however our flights usually come in at about 7 in the morning. Its the baggage claim that can take a long time. We come in through Terminal 2 all the time, as we travel as a family, we just go through whichever line is shortest, so we usually get through immigration really quickly.
When you come out of Terminal 2 arrivals, there is a Tim Hortons Coffee franchise. YUMMY