Went ahead and got the Graco 4ever DLX for our bundle of joy. So far I'm very happy with the product and seems like the baby likes it too.
Of all the seats I shortlisted, this one was the most expensive. But given the quality and usage options, rear-forward-extend back booster-only booster, i can easily use it for 10years(as per manufacturers) or more(as per people using it for 2 generations ignoring the manufacturer).
This seat is rock solid and heavy and somewhat big! Luckily, it sits easily in my Rapids boot when not in use.
The first day took me 1 hour of fiddling to understand various ways of using it. This seat can be used in almost any car as it supports 2 point, 3 point and isofix
Couldn't try isofix as both my Innova and Rapid lack the option, but both 2 and 3 way works perfectly and sits firm. It has different access slots for front/rear facing and also has a tether at the top for front facing(only in cars where there's tether option near the rear headrests).
All the attachable options are easy to remove and reattach. There's the water bubble marker to check the level of the seat which makes it easier to decide what level to use depending on the slant of the particular vehicle seat. If i remember correctly Rapid needs level 2 and Innova level 3. Please note that Rear and forward facing levels are different and the range is marked with blue and red color respectively.
After a couple of uses, now it takes me only 2 minutes to attach the carseat on both my vehicles.(Actually 1 minute to attach and 1 minute of my OCD trying to shake it up and see if it moves despite knowing it won't)
A couple of things I've been doing which helped:
Before latching the baby to the seat, i ask my wife to sit beside the empty seat and distract him while i latch him. This thing has 5 point harness, and everytime i do this, i feel as if I'm putting my kiddo in a formula 1 car seat lol. The baby sits snug and way more comfortable than in someone's lap.
Put the ac on and make the car comfortable before putting the baby in the seat.
Remove the sun blinds, as he enjoys watching the scenary outside. He loves watching other cars, mostly SUVs, as sedans are not in his Line of sight yet. And big trucks make his eyes go round when i move past them.
Experience:
Feels safe and comfortable and we've done 1 hour trips so far.
He dozes off in the seat naturally by himself. Wish this happened at home, sparing my back and saving me from doing the tribal dance to rock him to sleep.
The headrest support cushion dimensions are slightly large. He sleeps like we do in Mumbai locals, sitting straight and head lopsided, so i just make it more snug by inserting a cloth between the padding at one end. This keeps his head nicely cradled.
I tried putting the seat in the middle of the rear bench in my Rapid, with the 2 point belt. An adult cannot sit next to the seat, as the seat overlaps exactly where the passengers arm will rest. So the rear centre is a BIG NO.
This seat will occupy 1 complete adult seat, so effectively making my Rapid a 3 adults+1 car seater and the Innova a 5 Adults + 1car seater.
He sits on the middle captain seat in Innova, so 2 adults at the back can take turns playing with him and keep him occupied.
The bottom line is, I'm extremely Happy so far with the purchase, despite the high cost. My parents were sceptical at first, but now they see how beneficial it is, and even brag about his throne to their acquaintances.
Bikers and other cars get a glimpse of a happy baby in a car seat and I've caught him smiling at the funny faces people make at him through the window. I Hope this view creates more awareness for other people and encourage them to buy car seats.