I haven't driven 2012/2013 Punto yet. But, I did drive the Linea soon after the launch in 2012. I couldn't find much of the difference with respect to handling after the GC increase. Again, I am still hesitant to do the GC upgrade for my Linea. Reasons - - I feel Linea looks more elegant with lower GC. - I don't want to compromise even a bit on Handling and Ride after the upgrade. - I have driven in all sorts of terrains in South India with 161mm GC and I was able to manage it.