
Cosco Kids
Scenera Next DLX Convertible Car Seat
Super light, cheap, great for air travel, but outgrown fast.

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We've got a britax max safe pro and like it, up to 36kg.
Joie irvana max is great. You can harness up to 125cm and then use as a booster. It’s forward facing. For my youngest we got a britax max safe pro, which is backwards facing and cheaper than the others ones you mention
Not 100% sure, but I do remember the first edition of the Britax MaxSafe Pro had quality control issues with the pull strap fraying and fabrics being poor quality. At the time there were lots of people on the Facebook groups complaining and returning them. Britax released a MaxSafe Pro 2 that seems to have fixed these issues and other retailers still recommend and stock them. The main two admins seem to have gone all in on Avionaut - if you want an infant carrier they always say Pixel Pro or Cosmo, and ERF seat they always say Stardust and a booster they always say the Up or MaxSpace. My assumption is that the Avionaut margins might be higher, but maybe they genuinely think Avionaut makes the superior seats.
If you want long lasting rear facing for a big kid you'll want to be looking at Axkid, BeSafe Stretch or the Britax max safe pro2 (cheapest). They're all belt and tether (which does take some getting used to) except the new Axkid core. These are expensive seats unfortunately, Britax one is the cheapest, I have one and like it fine. If you're not worried about it lasting get a Joie stages but it's harness limit is 105cm so won't last a big kid long before it needs to switch to seatbelt which obviously isn't ideal if they're still young.
Not long. The support leg is easy, the seat belt can be a bit trickier to make sure it’s tight but it takes me 2-4 minutes maybe to move from car to car. My sons almost 4 and we’ve had the seat since he was around 10 months old. The specific seat we have goes to 25kg (my son is 18kg at almost 4) but it’s replacement (it got discontinued) I think goes up to 36kg so should last till age 7. It’s either the Britax safe way M or the Britax Max Safe pro 2, not sure as I said mine is an older model :)
We've got a britax romer max safe pro and it's good. It should fit our 4yo rear facing until she's about 7 because it's got a high weight limit. It's pretty easy to move between cars and they're often on sale so not a bad price. We've also got a besafe stretch which I prefer, but it is a lot more expensive and I wouldn't like to be moving it between cars, but it's great as a car seat that pretty much stays in one car. We'll probably buy another one of each when our 8mo grows out of her baby seat

Cosco Kids
Scenera Next DLX Convertible Car Seat
Super light, cheap, great for air travel, but outgrown fast.

Cosco Kids
Scenera Next Convertible Car Seat
Portable, affordable, quickly outgrown, airplane buckle discomfort.

Joie
Mint Latch
Easy baseless LATCH install, lightweight, but quickly outgrown.

Nuna
PIPA Series
High-end travel, easy baseless install, but very pricey.

WAYB
Pico™ Portable Car Seat
Ultra-light, compact travel, quick install, but expensive and outgrown fast.

Ranked #1
Cosco Kids - Scenera Next DLX Convertible Car Seat

Ranked #1
Cosco Kids - Scenera Next Convertible Car Seat

Ranked #1
Cosco Kids - Scenera Next DLX Convertible Car Seat

Ranked #1
Doona - Doona Series

Ranked #1
Cosco Kids - Scenera Next Convertible Car Seat

Ranked #1
Nuna - PIPA Series