That's a great device, thanks for sharing.
I've been struggling a lot lately with old tape player.
Battery dying, belt worning out...
Since I use tape with my synth, sometime you troubleshoot with no reason when the tape start playing quietly.
Definitely looking for something more solid.
Yes so the only issue I had with it was it ran slightly fast at first. So I put my calibration tape it and sure enough, fast. You can adjust the speed but the screw is on the front, under the transport, not on the back. So it's a bit annoying but doable.
There is another one, more expensive by "we are rewind". It has bluetooth even but it is even bigger so I'd say not wearable.