I'm sorry, but the last time I tried OpenCage it was terrible. And by terrible, I mean in line with everything else that uses OSM-based data. Geocoding is hard and I wish you luck, but you've got a long way to go.
Mapbox's geocoder (which mostly uses proprietary data) isn't quite there yet but is steadily improving.
The only guaranteed way to know if a service will meet your needs is to test, hence why we offer 2,500 free queries per day for as long as you like.
Happy geocoding!