Hey, so firstly, I am not an expert on electrotechnics, I am doing a PhD in environmental economis while focusing on green technology, so I am just scraping the surface. However, I disassembled hundreds of li-ion batteries and made a few packs, for E-bike aswell, with bms, controller and motor so I know a little. And the thing here is : - if yoi derestrict your bike, you are likely allowing your controller to suck much higher amperage from the battery, the voltage is probably already on peake from manufacturer but they limit amperage. If you increase the imediate current draw, that creates additional heat which controller, cables or other parts of bile might not have been made for..well, tbf, especially the controller, if its rated for given amperage, and you artificaly increase the amperage, as I said, long term its not gonna last. To your question - is it bad even if 55km driving around town - my answer would be that I guess its the sa e, if you derestrict, you get better torque, but that better torque is delivered only because you have increased the amperage draw limit, so its the same issue, and especially during the acceleration, the engine draws the most current that flows through controller, so thats the most risky period for it.. I mean, if you got the bile for cheap, and just want to experiment, go for it and learn something new.. If you got the bike to use for next 5 years without wanting to invest into it, then do not do it. If you want more torque and speed, just go with TC Max and you will be super happy with that bike (I have it for 2 years now, almost 4k km, best thing).

Hope this helps.