[DCEite]

Very simple.
As someone said, if chauffeured, than Indica is a no brainer. The backseat of WagonR is pathetic, the comfort levels are no way near Indica.
However, if you or your father is going to drive everyday, the WagonR DUO makes for a great choice, being light,nimble and quick, and having effortless power steering which makes city driving a breeze.

Regarding highway manners, yes the Indica is a lot more stable than the tall boy, but the WR is not as bad as you might think.

Cost of spares, very cheap for the Maruti. Rock solid reliability as well. Can't comment on Indica, as i havn't owned one. But heard that things are improving as far as build quality and reliability is concerned. The cost of spare parts are dirt cheap though.