You should check out Toronto's, then. Although the subway is limited (only two lines -- the Toronto Transit Commission relies more on bus routes), they're as clean as a butler's kitchen.
I only wish the route design was more elaborate like NYC's.
BlueWizard's blog: The Rambling Corner
HEDWIG: "The road is my home. In reflecting upon the people whom I have come upon in my travels, I cannot help but think of the people who have come upon me."
I have been pleasantly surprised by the subway system by me in NYC. I only take the 1/2/3/9 on a regular basis, and occassionally the B, D (only to yankee stadium), and C. And I haven't had many issues with it, except it being cold and wet and dirty in the winter, and too hot and dirty in the summer.
The Montreal subway system is quite good -- I lived there for a month, and took it everywhere. Unfortunately, they didn't seem to have air conditioning when I was there in the summer -- and the humidity was WAY worse than NYC. Otherwise, I was very impressed with their system.