I've ridden in the country that requires stvzo lights. When riding on the bike path, there is a big difference when passing oncoming cyclists who are using compliant lights and those who buy imported non compliant lights from eBay or Amazon. Those who are using non compliant lights are extremely blinding and I have to stop and look away until they pass because I can't see anything in front of me.

Some of the compliant stvzo lights have surprisingly very wide beams. There are reviews on blogs making comparisons.