Convertible car seat

What is the best car seat for a small sedan?? My baby’s outgrown her nuna pipa seat and we’re looking for a good convertible seat that will fit in our BMW sedan. I’ve seen good things about the graco extend2fit but am looking for more options too! One that swivels would be nice but probably wouldn’t fit with our car. Anyone else with a sedan and convertible car seat please share suggestions!