All four are classic pedal moped platforms (not modern scooters).

BikeDriveOilGood forGuide
Puch MaxiChain + centrifugal (E50)PremixParts support, kitsPuch guide
Tomos A35/A55Chain + 2-speed autoPremix + gearbox ATFLater US survivorsTomos guide
Honda ExpressChain + centrifugalOil injectionReliable if pump healthyExpress guide
Piaggio CiaoVariants; pedal moped familyTypically premixItalian parts ecosystemCiao guide

Ready to buy? Budget checklist · Buying guide.

Parts ecosystems matter more than brochure speed. Maxi and A35 support is broad in the US; Express needs oil-pump literacy; Ciao rewards people willing to source Italian bits. Pick the bike you can actually keep alive in your town.