Between the two, if you are looking for something more premium and newer, we would suggest going for the Kia Carens Clavis in the HTE (EX) variant. It is the newer of the two and is also larger, offering a greater sense of space. Overall, it feels more premium and upmarket both inside and out.

In terms of equipment, both cars are fairly well equipped, but with different highlights. The Maruti Suzuki XL6, being the top variant, offers features such as leatherette upholstery, ventilated front seats and alloy wheels. The Clavis, on the other hand, is offered with a sunroof, which the XL6 does not get.

When it comes to performance, both cars are quite similar as they use 1.5-litre naturally aspirated petrol engines. While the Clavis has a more powerful engine on paper, it is also the larger and heavier car, which reduces that advantage in real-world driving. Where the Clavis clearly stands out is engine refinement and sound insulation, where it feels a notch better than the XL6.

Between the two, if you are looking for something more premium and newer, we would suggest going for the Kia Carens Clavis in the HTE (EX) variant. It is the newer of the two and is also larger, offering a greater sense of space. Overall, it feels more premium and upmarket both inside and out.

In terms of equipment, both cars are fairly well equipped, but with different highlights. The Maruti Suzuki XL6, being the top variant, offers features such as leatherette upholstery, ventilated front seats and alloy wheels. The Clavis, on the other hand, is offered with a sunroof, which the XL6 does not get.

When it comes to performance, both cars are quite similar as they use 1.5-litre naturally aspirated petrol engines. While the Clavis has a more powerful engine on paper, it is also the larger and heavier car, which reduces that advantage in real-world driving. Where the Clavis clearly stands out is engine refinement and sound insulation, where it feels a notch better than the XL6.

Overall, if you are choosing between the two, we would recommend picking the newer Carens Clavis over the Maruti Suzuki XL6.

If you travel mainly on the highway, you need an MPV with a strong engine for easy overtaking and cruising and for your budget, the Kia Carens Clavis HTE EX with a 1.5 turbo petrol is best for your highway runs. However, for your budget, you will only get a manual option and not an automatic, which may not be convenient for city driving. 

If you only want an automatic, then your best option is a Maruti-Suzuki XL6 Alpha, which comes with a smooth torque converter gearbox. The XL6 lacks the punch of the Carens Clavis turbo, and you need to work harder to overtake on the highway.

The Maruti Suzuki XL6 would best suit your requirements of mileage and performance. Against the others in your shortlist, the 1.5 litre petrol engine in the XL6 offers decent performance and refinement, but a noticeably better fuel efficiency. The engine has a mild-hybrid setup and, in our standard test cycle, returned a figure of 9.2kpl in the city and 17.0kpl on the highway. 

We assume, of course, you are comparing petrol versions across the three MPVs in your shortlist, given that the XL6 comes with only a petrol engine. If not, the Kia Carens and Hyundai Alcazar also have diesel engines, and these versions would be more fuel efficient than the petrol XL6. 

Since your priority is third row space, it would come down between the Maruti Suzuki XL6 and the Kia Carens Clavis. The Hyundai Alcazar does have a third row, but it isn't as roomy as the other two. 
The Kia Carens Clavis has the edge when it comes to features and equipment, a plush cabin with a premium feel and a more powerful engine.

However, the XL6 is an excellent value considering what it offers for the price. If you seek performance and features and don't mind paying extra, the Clavis is a very good choice.

However, if you can make do without the jazzy interior and want a predominantly spacious third row, the XL6 would be a good choice.