The Alto 800 LXI is a great car to drive in heavy traffic. It is easily manoeuvrable and no space in the road is too narrow for it. The price is extremely reasonable as well. I have driven 32000 km in it so far and have never found a reason to feel dissatisfied until I drove a Celerio AMT, which has a more powerful engine than the Alto 800. However, that apart, the Alto 800, as I mentioned before, is a great car to have. It is extremely fuel-efficient too.
I drive the car on extremely steep slopes and around sharp bends and have always experienced total control (touch wood). I have even driven it, occasionally above 100kmph on the highway and not had any issues.
Periodic maintenance should not have been expensive, but, now that the car is almost 5 years old, the costs are going up, goodness knows why considering the parts are all made in India.
It is a tiny car but the available legroom and boot space is enough for a small family.
Overall pros are, that it is compact, fuel-efficient, reliable and service centers are widely available. The only con is the rising servicing cost as the car ages and questions regarding the quality of service.