Belt drives are not new inventions.The belts that are used on bicycles are the same timing belts and gears that have been used in industry for 60+ years.

The only difference between those and ones used on a bike will be the exposure to the sun.I wouldn't worry to much about that,just change it every 60-70,000 miles and you'll be fine.

These belts are strong,they don't stretch....they can take a beating.

A quality timing belt(Kevlar thread) has a breaking strenth of about 150lbs per 1/8in of width,they're strong!

I like them,I'd buy one today if I wanted one.