We got a Pebble and Familyfix base from amazon in 2014, with the plan to move DD to the Pearl when she was big enough. Since then they've brought out the 2way Pearl (which annoyingly needs a 2way base) which can rear-face with bigger children.
So we've just bought the 2way Pearl and base (from kiddicare, as John Lewis fucked us about with trying the seats in our car) for DD. She has had 18 months use out of the Pebble, though, and we're going to use it again for DC2 (due in March), so it'll have done it's time!
When DC2 needs to move up a seat we will probably get a Pearl for DD, so she can start forward facing at the same time as DC2 moves into her 2way Pearl, and then DC2 can have that one facing forward facing in due course.
That's the plan, anyway! I think the 2way base, Pebble Plus and 2way Pearl should be a good bet for the future, they'll meet i-size regulations too so ERF will be fine. Definitely try the seats in your car, though - they'll probably fit fine, but you'll want to make sure driver/front passenger has enough leg room.
I think MaxiCosi are a good bet, anyway, there must be a reason why they're the most popular car seat manufacturer in Europe.