More feedback after several trips.
One seat lost its shape - became more like a ball so have to underinflate to use. Overall the seat surface area is small so they are not the best choice on longer rides - kids complained a lot. I found them sliding and leaning in some awkward and probably unsafe ways on numerous occasions.
I ll continue using them for the convenience of not having checked bags but bring regular boosters to trips with a lot of driving or where i have checked bags anyways.