Did you know that it's faster to travel from South Kensington to Kings Cross via the District/Circle then Victoria lines than the direct Piccadilly route – provided changing at Victoria takes no more than 4 minutes. People attempting this are recommended to get in the second carriage of a District train near the central doors (or the rear of the first carriage of a Circle train, which are shorter) for optimal placement at Victoria. The exit at Kings Cross is at the very rear of the train. Unfortunately I still just missed my train to Cambridge, but that's life.
I did however get to travel on one of the refurbished District trains, and they're a vast improvement. Doubleplusgood marks for Metronet and LUL here.