gerg said:The Tokyo subway isn't necessarily cheaper, depending on how much you travel. With an Oyster card, which I believe can be picked up easily for tourists, there is a maximum amount of money that you can spend a day. (I believe that this is the price of a one day travel card.) If you travel a lot on the Tokyo Metro, however, you can easily end up spending two times or three times that limit.
Also, again, the culture in Tokyo is nice, but Tokyo's National Museum doesn't really have much against the British Museum.
Assuming a Japanese tourist knows about how to buy an oyster card. My experience even with English speaking tourists is they just drop the four pound non-oyster penalty fare or whatever to ride the tube because they don't know what's going on (and no real sense how much four pounds is worth). Plus the oyster equivalent in Japan can be used at resturants, shops, etc). Also, the tube closes entire stations and even lines for 'engineering works' on weekends or whenever the feel like 'updating their victorian infrastructure' so that disqualifies it from being the best mass transit system.
I would say one of the best cities for museums is Washington DC. They are also free. Sure the british and VA museums have an extensive collection, but i didn't think it was presented very well. The tate modern turbine hall was so cluttered, it felt like someone's closet of giant art.