A 20-vote Labour gain from the Tories. Last result turned out to be a cliffhanger!

http://www.bbc.com/news/av/election-2017-40229722/kensington-goes-to-labour-nearly-a-day-after-polls-close

The first past the post system ain't perfect, but in Blighty the 2 major parties retain it instead of changing the system to one of PR = proportional representation. That system ain't perfect either. The reason that FPP is preferred by the 2 major parties is that it will give them more seats and squeeze out the other parties.