Hopefully someone who currently owns an Aiwa / Medion / Leotec gets one to compare their sound. If I knew someone who owned one close to me, I would be strutting up to them with my Aiwa like Radio Raheem...

If it outperforms it, I would be impressed enough to bow down in defeat

but it would have a lot to prove for the price. It already lacks in features. Cassette mech is likely identical to the Chinese boombox but the China-box was only $249 with built-in in AM or DAB/FM radio, cassette, CD, Bluetooth, USB/microSD and, while smaller, has back-lit VU meters too. The highs on my Aiwa are every bit as crisp as my M90, it thumps quite well and goes very loud. I have not dared to punish my M90 and risk tearing an aged speaker in competition, but I am willing to bet my Aiwa would beat it even back in its heyday. Of course technology has improved in amps since then. Even in budget models.
I would have to hear one of these to see where the extra cost is. The specs I have seen seem to indicate it has 100 watts RMS however, I have learned to be skeptical of going by watts alone in retrospect to overall sound quality. I have heard lower wattage units outperform higher wattage models. They seem to indicate that the cassette has an active erase head. Now that is a huge plus. If it has a nice set of speakers and amp with a tuned enclosure to go with that RMS wattage output, it should bounce itself off a shelf.
It reminds me how much specs only tell part of the story, the same way a good
live streaming app development company has to go beyond raw features and actually optimize for the real-world experience.