Out of the box the guitar sounded like trash - most notes played at reasonable volume were accompanied by annoying buzzing, not from the neck/frets but from the body. To investigate I took out the electronics, and the buzzing stopped. After a few experiments I figured out that the cable connecting the jack and battery to the preamp was the cause. This cable is routed through a cable tie on the bottom of the body, and was fixed in a way that caused it to press against the top with the battery case inserted.
This could be resolved by simply pulling a bit more of the cable through the cable tie (in the direction of the preamp) so that it doesn't reach the top anymore, and now the guitar sounds great.
Playability and optics are great. The built-in tuner is cool as well, but could be a bit more accurate - the interval below/above the actual pitch where it shows the string as being in tune is rather large. I've not tested the pickup yet (except for a very quick check to see if I get any signal) so I don't have an opinion on the pickup and preamp for now.
All in all it's a good guitar, almost ruined by garbage quality control. I'm glad I decided to investigate the buzzing instead of sending it back as it was easy enough to fix, but that should not be neccessary for a 700€ guitar. So 1 star for quality as I had to open it up to make it playable, and -1 star total.
As an aside, I have two guitars from Japan (Fender JagStang, Fender FFXIV Strat) and three from Korea (PRS SE 24, Strandberg Boden OS, Cort Viva 7) which were all fine out of the box. But all three "made in Indonesia" guitars I own came with really bad QC issues. First a Strandberg Boden NT where the wood was improperly dried so the fretboard shrunk to the point of being unplayable due to heavily protruding frets in a few months (SB support said it was my fault due to too low humidity, my hygrometer and 5 other guitars in the same room say otherwise. Guitar tech commented it was the most f'ed up neck they've ever seen). Then the Ibanez ICHI10-VWM Ichika Nito signature, which is great except for the fact that it arrived dirty - grease on the strings, some sort of glue on top of the neck pickup, and the back looks like it's been dragged through mud prior to clear-coating (the front is pristine, otherwise this would have gone back immediately). Now the TOD10N with buzzing from the factory. The next time I see "made in Indonesia" on an instrument I want to buy, I'll be asking Thomann to double check it before sending it out, as it seems I can't expect the manufacturer to do so.