Yes, the Tata Sierra will meet your requirements of safety and comfort very well. In terms of active safety, the Sierra has good grip around corners and good high-speed stability, too. The safety equipment is also elaborate with 6 airbags, electronic stability program (ESP) and after-impact braking standard across variants. 

The Sierra is yet to be tested at either GNCAP or BNCAP; however, Tata Motors says the car is designed for a good rating and given the company's track record, this should be the case. As for comfort, the ride quality is good, and there is ample space inside. The seats, too, are comfy and at the rear, there's enough space for three to be seated in comfort. 

Your observations are correct. Neither the Tata Sierra nor the Kia Seltos has been crash tested by Global NCAP or Bharat NCAP yet. But Tata Motors cars have had a good track record with these tests. While the Kia Seltos uses an all-new global platform that should be safer than the outgoing model.

Both SUVs feature the latest in active and passive safety features, which should be a reassurance, and thus, on the safety front, you won't be wrong to go with either. As for other factors, the Sierra is certainly the more spacious of the two and edges the Seltos out on comfort as well. 

However, in most other areas, it's the Seltos that comes out on top, including, as you have pointed out, after-sales experience. The Sierra is being produced at the ex-Ford plant in Sanand, Gujarat. It is said to have higher manufacturing standards, and the brand has been committed to improving its after-sales service across the country, but the results of that will take some time to show.

If you are looking for an SUV with a good luxury feel, we would recommend that you look at the compact SUV segment instead of the mid-size market. While you will get mid-size SUVs for under Rs 15 lakh, they will all be the lower variants, which will not look or feel very luxurious. 

The best options here would be the Kia Seltos and the Tata Sierra. However, as we mentioned, if you do look at a segment below, you could get a Hyundai Venue, which has a very premium cabin in both look and feel and will be very well equipped too. This is the SUV we would recommend to give you that luxury feel at your price point.  

The new Tata Sierra and new Kia Seltos are both excellent 5-seat SUVs packed with the latest features and tech. The Tata scores high on space and ride comfort, while the Seltos is big on quality and driving dynamics. 

However, at this price, you could get a 7-seater too. If you don't mind the MPV body style, the Kia Carens Clavis offers the most spacious and practical cabin and is available with several different engines and gearboxes. 

If you would like an SUV body style, consider the Hyundai Alcazar, though its third row and boot aren't quite as good as the Kia's. 

The Tata Sierra diesel is the most popular variant right now and accounts for 50 percent of the bookings. If you follow basic DPF regeneration protocols like a 25-30min long drive at a steady speed of 50-60kph every month or so, you shouldn’t have DPF problems. 

Also, unlike the Kia 1.5 diesel, the Tata 1.5 diesel in the new Sierra is not known to have major issues with DPF clogging. So go ahead and buy the Sierra diesel.