Well, I bought both Kymcos new and I know that crack in engine block, broken speedo cable, poor bottoming out rear suspension, squeaky/squealy front brake and rear suspension that cannot be lubed and rusty sub-quality assembly parts are Kymco's fault in case of People 250S, all in the first 7000 kms and was lucky to fix them under warranty.
A125 had a few glitches too (fuel gauge, dead starter button, steering column that likes to unscrew itself, moisture in cables that renders it useless under sub zero temperatures because rear brake and gas cable get frozen solid...), but nevertheless it seems to have better overall build quality than P250S.
In the past I had Kymco Cobra 50 Cross that had a problem with variator: it would take ages for scoot to go from 20 to 50 km/h, and this issue could not be solved by several mechanics who tried every trick in the book.
Overall, I have to say that I do not have that good experience with Kymcos. The problem is that I do not have idea what should be a "good scooter brand" that is trouble-free so I stick with this brand.
In the past I had some bikes that were completely trouble free: for example, Peugeot Zenith 50, Yamaha TW125 and Kawasaki 750 ZR-7S.
With Kawa, I did not have a single issue in 26.000 kms and 3 years! Ditto for Peugeot.
With Yamaha, I had to change a battery once.