I bought a $50/yr subscription to Busuu and never looked back. Long time Duolingo user. It's a good app but a bad product. Busuu on the other hand feels easily worth the money if you're actively learning with it, and you can get quick feedback from native speakers in their community (and give others feedback which is just as rewarding.) I haven't used Duolingo in a while so maybe they've added similar features, but if they haven't they're seriously missing out on the community effect of language exchange.