You’re probably hearing the difference in wood vs. plastic. (Did you get the “Ecodear” Yamaha? Supposedly the Ecodear models sound a little closer to wood.)
I’ve done a bit more research on the Hohners. What I’m seeing are reports of decent tone, but some intonation problems on certain notes (F and E♭ are mentioned) and some difficulty in playing notes in the higher registers. I’d be interested to know if you find any issues in those areas, specifically.