Well let me try my best to put my inputs on the above cars. I can give the best input on the Etios (petrol) as i personally own one for the last 2.5 years.
Toyota Etios- I own a petrol but i have driven the 1.4 D4D engine. The diesel is good to drive in the city with minimum turbo lag. In the highways above 120/130 the car looses its steam. The steering is light, brakes are supper effective but i found the clutch to be on the harder side compared to my petrol Etios. With the new stiffened suspension the cars handling improved significantly. So for self driving its a decent car. Now coming to the rear seat comfort. I can say its a comfortable car. The Ac is decent. The NVH level of the new Etios improved a lot compared to the older ones. The way it glides over the pot holes or the rough patch is quiet impressive. But the Verito is more comfortable on the rear seat. The interiors of the Etios is very bare basic. You wont find the premium feel of the club class sedan (Manza). In one word Etios can be best described as a practical car. The interiors are basic but very functional. Space is no bar too. One can comfortable seat on the rear seat with crossed legs. Now coming to the point Etios is build to cost. Yes its very true. The car thoroughly lacks the premium feel. But its a no nonsense car. The service costs are the cheapest of the lot. Maintaing my Etios is less expensive than maintaing my Alto K10. The service Toyota provides is really good and they leave no room for complaints. So if you are looking for a hassle free comfortable and spacious sedan with good service back you can close your eyes and opt for the Etios. I have a niggle free ownership with my Etios for about 2.5 years with nearly 28,000kms.
Mahindra Verito- I never drove a Verito but had been a rear sear passenger on this car many time for the airport runs. In one word i can say its a very comfortable car. The AC is good too. What i observed is the cars has minimum turbo lag and once i got a very enthusiastic driver. On a open stretch i saw the car cleanly pulled till 130. After that the driver had to slow down due to traffic. I know one driver in Bangalore who used to drive a Verito for Meru and later he switched to an Etios for mega cabs. I always take him and have is phone number too. Once i asked him to compare Etios and Verito. His comparison was like-
1) Verito felt more powerful. (In specs both the cars are similarly powerful so i gues the drivabilty of the Verito is better than the Etios.)
2) Etios has much better brakes.
3) Maintenance cost of Etios is less than Verito.
4) Mileage of Etios is more than Verito.
5)Comfort wise he told Etios is more comfortable. ( May be thats for the driver but i would say rear seat comfort of Verito is slightly better than the Etios. Its has got a more poised feel over the rough patches.).
Nissan Sunny- I never drove one nor did i seat in one. So no comments.
Chevy Sail- I never drove one nor did i seat in one. So no comments.
Honda Amaze- This is a car which i love a lot. 100ps power with 25km/ltr sounds really awesome. I once took a TD of this car. The power delivery is linear. Its a nice car to drive. Being a sub 4 meter car its more easy to drive and park compared to the other cars mentioned over here. On the flip side what i noticed is the NVH level was a bit on the higher side. The rear seat space is less compared to Etios/ Verito/ Manza. The car is a bit more bumpy than the others over here. Its a pure drivers car. So if your prime decisive factor is the rear seat then its better to rule the Amaze out.
Tata Manza- I have been in the rear seat and drivers seat both on this car. Its one of the most fun to drive when the turbo Kicks in. Unlike the Amaze it gives a sudden rush of the adrenaline. Where as the Amaze feels more of a tamed car. The Amaze is way more easier to dive than the bigger Manza. The Manza is really a big car to drive in congested cities. The interiors of the Manza is no doubt the best. In the rear seat it felt as if i was seating on a sofa. But still on rough roads the vertical movement was there. Which is better controlled in a Etios/Verito. As a chauffeur driven car i liked the Manza. But my friend who owns the car has referred to few niggling problems. For example with in 15,000kms he had to change the clutch plate. Left side suspension needed overhauling at 21,000kms, there was a minor issue with the steering too. But all were rectified by Tata to his satisfaction. I must say Tata has improved a lot with the Manza.
So at the end i would say all are great car. Best thing will be you take test drives of all the cars with your parents on the rear seat. So they can judge the comfort level and the feel good factor. If i were you i would pick the Etios due to its over package. (I tried to be unbiased but still suggesting you the Etios.
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