Lumintop FW1A discussion and review

The FW1A is a very attractive light. Something I don’t understand that I hope someone can answer.

Researching the SST-20 variety I don’t see any output tests, but illumn.com advertises a maximum output of ~700Lm on their sales page. According to maulka’s SST-20 output tests, the only data I can divine is ~700Lm is ~2.5V.

I understand the step downs with FW3A. But why does FW1A light step down so fast at a maximum of 700Lm? Why can’t it sustain 700Lm with a decent 18650 cell for at least a few minutes, if not half an hour? What am I missing! Thank you.