"reliable" can be qualified. Always run, never leaves you stranded...? or always runs well?
Over time I've put many thousands of miles on three Puchs, often a long way from home, and never once been stranded. But im a macgyver, and Puch mopeds are so blessedly simple that you're never more than a random paperclip to get back on the road. But I have to say that low grade simplicity means that the fuckers never, ever run the same way two days in a row. Often not even on the same ride. The Puch is too much a slightly upgraded toy to hold its "tune" for long.
Not to rant but the 12mm Bing is better suited to a child's mini ATV that never leaves the yard than any "reliable" form of transportation. There was already far superior front suspension on many mountain bikes by 1984 than on the Newport! Yikes! Triple crown that always loosened unless you overdrive the bolts, handle bar clamps same story, hell, every fastener on the bike. Still, never left me stranded. So there's that. But puchs are my only personal reference.
A neighbor rereconditions scooters and peds for hobby. I've seen various yamahoppers, hobbits, Vespas, and others up close in various stages of rebuild and almost always been impressed by the difference in build/component quality compared to my puchs. The carbs, forks, castings fasteners, hand controls, etc, much much more 'motorcycle' level of quality. My Newport is something halfway between Schwinn and Yamaha.
Not sure what I contributed here. Just some thoughts (edited)