The London Underground is a good sometimes. Half of the Jubilee line has beautiful, with modern stations (just get on att Canary Wharf) , the Victoria line is fast and is getting new trains soon. The District line is getting trains with AIR CONDITIONING, and the Waterloo and City line really is the cheapest roller-coaster ride in England.
But you dont hear much of the Underground's unloved cousin, the DLR. OK, the trains are ugly, and its stations are basic and mostly 99% overground, but you get a great view from the driverless trains, its faster then you'd expect, runs a bit later then the Underground, and is very reliably and punctual.