Hi there

I have a two year old and he got his own seat on the plane with just the regular seatbelt that adults use....it seemed fine to me.

Also, I live in Singapore, and to be honest, you are never in a taxi long enough to necessitate harness/strapping them in like you would at home. Singapore is pretty small! My DS usually sits on my lap and I put the seatbelt over him (the lap bit) and the shoulder bit goes behind him, and over me IYKWIM. SOmetimes he even sits in the middle with his own seatbelt.

I am always really careful to have my arm ready to hold him back if the driver does a quick brake....and some of the drivers can be pretty dodgy (no indicators to change lanes etc) but you can tell them to take it easy too.

Happy Travels