Tiffin food carriers / lunch box?

http://importfood.com/foodcarrier.html

I have been thinking about Tiffin food carriers as an alternative to other "lunch box" options. How practical are these in the USA? One thing I also wondered about was keeping hot things hot and cold things cold. Do people in other parts of the world only keep hot things or cold things in them for any single meal? Since I typically pack my lunch 5 hours before I eat, I also wondered about food safety.

Maybe I'm better off using the plastic containers that seem to wear out and get thrown away after some use that are also easy to microwave.