I traded in my 2005 Maruti Swift VXi for a 2011 Swift ZXi a month ago.
There are some things about the new car that are nicer—the rear wipers
and alloy wheels are especially welcome, and the height-adjustable seat
belts are a nice touch. Mostly, though, the car is the same as the old
one.
The only dramatic change is the new K-series engine, which is supposed
to be lighter, with better fuel efficiency and lower emissions. Despite
its slightly smaller 1197cc capacity, the peak power and torque figures
are similar (85PS@6000rpm and 113Nm@4500rpm). The engines perform very
differently, however, as I have learned over the past two thousand
kilometres. (It's too early to say anything about fuel efficiency,
though.)
(Aside: the official Maruti Swift
web site—which should have been able to give me the specifications
for engines both old and new—has been given over to a stupid "hold your
breath" splash page for the new Swift to be introduced later this year.)
The new engine is louder and higher-pitched (annoyingly so) with the
throttle open. The power curve has been shifted to the left, resulting
in noticeably more low-end torque (which makes city and hill driving
easier). The disappointing corollary is that highway performance is
compromised by the loss of power at the high end.
Given a good road, my old car seemed eager to go up to 140kmph, and it
accelerated nicely past 100kmph even in fifth gear. The new car begins
to feel reluctant at 100kmph, and needs a lot of coaxing to move up to
120kmph. I had to keep shifting down to fourth or even third gear while
overtaking cars on the highway. The old car also felt perfectly stable
at 120kmph, while the new one feels a tiny bit flaky beyond that speed.
I know that conditions in India are rarely such that one can drive at
120kmph for any length of time, and one can take advantage of extra
low-end torque more often, but I can't help feeling a bit disappointed.
I wanted a Swift, dammit, not a heavily-laden swallow!
Update 2012: The stability problems went away when I switched
from the stock JK Vectra 185/70 tires to Yokohama A-Drive tires of the
same size. The car handled better, with noticeably less road noise, and
felt so much more stable at highway speeds. I guess the stock tires that
worked for the LXi just didn't suit the slightly heavier ZXi.