Advice, please - recommendations for a second car seat

[Nyborg]

My DS has just turned 1 and is in the Britax DualFix. We used a BeSafe IziGo until he outgrew it recently, and we've been delighted with both.

We now need a second seat for occasional trips in my parents' car, and I'm looking for recommendations. Ideally it would keep him rear-facing for as long as poss, but we could live without Isofix and as long as it's safe, I can live without the things that made us love the main car seats - swivelling, magnets in the straps etc etc. I don't want to sacrifice safety for price, but this car seat will get much less use so I don't want to spend a fortune.

Any ideas? Thank you.