Chozzle I didn't find your post aggressive at all and I know I can definitely be aggressive so no need to apologize! I actually just think you are wrong :)
To be a bit more practical in the discussion for those looking for a safe car seat that can be used belted rather than on an Isofix base Which highly recommends the Britax Römer Baby-Safe Plus II SHR.
This car seat has a 5 star crash safety rating front and side used both with a base or without a base. Both versions of the car seat are a Which best buy and there is zero crash safety difference between the car seat regardless of how its strapped in.
This is the car seat DH and I are choosing because in addition to it getting the highest possible safety rating available on Which for any type of car seat, its also compatible with the Bugaboo Boo 3 for use as a travel system.
Given our lifestyles, we need a travel system and we need an urban buggy like the Bee3, hence how we've made our choice. Like I said, there are so many things to way up, that without taking absolutely everything into consideration, its hard to recommend what is appropriate for others on this really tricky topic.
But in our situation, nothing about our choice has any true safety implications for our daughter.