Its almost 5 years using tata nano CX. I bought this car because my budget was around 2 to 3 lacs and at that time options are few like maruti alto.
Tata nano got much good space inside then alto. nano have very good ac, Front Power Windows and it give me mileage around 22 in city and 25 on highway(without ac)
Interior space is very good. In back seat three people can sit very comfortably compared to maruti alto.
Driving Experience is very good with this car if you dont want to go higher then 70 kmph. after 70 kmph you do not get much confidence.(IT can go upto 110kmph)
Normally people doesnt like engine sound of nano and yeah its become sometime annoying in back seat. you cannot hear any sound at front seats but when you close all windows then at back seat you hear some continuous sound like bhrummmmmmm.
Mantainance is lower as its price.
If you budget is around 2 lacs then you should buy tata nano
If you are thinking about buying Maruti Alto then definitely take a test drive of nano and sit at back seat of nano and try it with alto. you definitely feel difference. nano is much spacious inside.
Now its also available in cng variant. so cost per km also very decreases.