I live in small town on NZ coast. Air is very clean. Mosquitos and neighbor's wood burners don't care. ERV is top 3 item in my house (other than induction cooktop and Japanese toilets).
Haven't heard of them from grand-designs and those kind of youtubers)
just some ideas what some (public)/most (nice home) japanese toilets offer, which might be hard to come by anywhere else
They are $200-300 online. Not Toto quality, but plenty good enough.