I’ve always been a big fan of the Santiago metro. It get you most of the places you want to go – especially if you are a tourist – it’s clean, it’s pretty cheap and efficient. OK – it gets bloody crowded during peak hour, but then which public transport system doesn’t suffer under these circumstances.
The main problem is during summer – especially on Line 1 (the main line) – where they really struggle to keep it cool. Love their “solution” for the platforms – spray mist over passengers 🙂