Actually these are the buisness tricks set by paksuzuki.
There is no much price difference as their milage i.e. Economy difference.
If you talk about swift then why you are ignoring Honda City while there is also not much price difference which also have a Di-Gi.
If you think like that there is no much price difference b/w Mehran and Alto, Cultus and Swift, Swift and City then you always confused. The decision should be upon your need, choice and money.
The Shape of Cultus is old which expire in Japan in 1993, it need to be replaced.