Ask HN: Recommendation for water filter/reverse osmosis system in UK?

Getting a new kitchen, and considering an under-sink filter or reverse osmosis (RO) system for drinking water. I'm in the UK. My goal would be to eliminate/reduce nasties in my family's drinking water — things like microplastics and PFAS. Problem is, while I don't trust my ridiculous private monopoly water utility (Southern Water), I trust random filter or RO system providers possibly even less. Does anyone have experience/expertise in these systems? Can anyone recommend something that they have evidence makes their water safer to drink?