i thought my Seca 1700 is using low currents getting only 300 lumens per LED where the LEDs are XML sized, and probably are XMLs.

but now i see this:

Supernova E3 TRIPLE quality features

this light only claims 210 Lumens per XM-L2 LED !

on the other hand Chinese lights ( and Lupine, which is a Chinese light in disguise ) produce about 600-750 Lumens per XML.

why such discrepancy ?

Supernova E3 - 210 Lumen / XML
L&M Seca - 300 Lumen / XML ( maybe it is not an XML, but it is a comparable LED based on size )
Dinotte 3 XML light - 500 Lumen / XML
Lupine Piko - 600 Lumen / XML
MagicShine 808 - 650 Lumen / XML
Lupine Wilma - 700 Lumen / XML
Lupine Betty - 750 Lumen / XML
Baja Strykr - 900 Lumen / XML

i think it is better to achieve same output by using more XMLs rather than by driving few XMLs harder. but it would be good to know exactly how efficiency and longevity of the LED is affected by drive current.