Since I have driven both cars, a detailed comparison from my side:-
+Better Built Quality
+Features missing in swift
Airbags + pre-tensioners,
rear wiper & washer,
Passenger side seat belt warning lamp
+Durable car with an award winning engine
+Better leg room for rear passenger
-Smaller engine (1.0 Less power)
-A/C is less effective
-Noisier than Swift
-No alloys or fog lamps
-No speed adjustable intermittent
-No split folding rear seats
*you have to be careful when buying a used vitz, often the odo is tampered and at times hit and repaired cars sent from Japan are passed off as totally clean cars here...be sure to inspect carefully, check auction grade when buying a vitz and buy from someone honest.
+Brand New Car with 2 year warranty
+1.3 L engine (More power)
+Car has good reputation globally
+Effective A/C ***
+Less noisier than vitz
+Features missing in vitz
Split Folding rear seats
Adjustable speed intermittent wipers
EBD along with ABS (vitz does not have EBD)
-No Airbags (biggest shortfall)
-Somewhat lower built quality (Although quality is decent for a local vehicle)
-No auto transmission available
-No rear wiper+washer
-No retractable mirrors
-Lesser leg room for rear seat passengers
I found the drive of both cars to be comparable so its a tie as far as the drive is concerned. Both the cars have a comfortable drive.
However, surprisingly I found the swift to be less noisier.
***I also found the swifts A/C to be more effective . However, it might have been due to the condition of the a/c of the vitz I drove. If anyone else can compare this factor also it would be great. Logically it also seems that swift would have a more effective A/C due to a more powerful engine.
Spare parts of both cars are also not an issue so not taking them into consideration during the comparison also.