Cheapest is to walk, though god knows when you get there...
Generally, it saves the environment mainly due to the energy
consumed per person per km travelled. Of course a bus consumes more
energy than a car (with it being a heavier vehicle), but consider
the number of cars not used when the car users switch to bus.
I doubt anyone really cares much for the environment (except for
the young green yuppies) since most people I know would very much
prefer a car. Think of the convenience to go anywhere and NOT
having to worry about the LAST bus/train! But in some instances
when parking and traffic jams are major headaches, having a public
transport is more convenient. No need to worry about where to park
your car or worry about accidents/scratches while being caught in
the jam.
As for from JKN to CGA, MRTs win hands-down. Generally, my
personal rule is any travel involving 4 stations' distance or
more will be faster on an MRT. (Different people have their own
rule of course)
i ever been cycle from Lakeside to Tampines follow the elevated
tracks.., underground track follow the outram park, chinatown,
clark quay, bugis and lavander..
its take around 5hr without rest, 6 hrs with rest
from lakeside 1.15am to 6.20am tampines
next day Tampines 1am to 6.10am lakeside
