What is the warranty period for Alternator ? 5 years ?

I think I can answer your questions as I have driven the Cerato 2.0 for more than 3 years

1.) no problem in this car except the minor rattling sound come from the area near clock and screen. no steering rack issue so far (touch wood)
2) Never encounter the issue of idle engine vibration.
3) For my case, FC is not good in 90% city drive 8.5 ~ 9.0km/litre but I am able to achieve 6.2l/100 km (~16.1km/l) for outstation drive with average speed of 130~140 km/h