Joye 510 mega xl has same life as 808 standard (280mah) but is 8mm longer with a carto (8mm longer than KR808D-1 standard but you are going to need an adapter with the 808)
Since the 2.0 carto will generate more watts on an 808 than on a 510, wouldn't it use up an 808 faster than a Joye Mega xl?
Since the 2.0 carto will generate more watts on an 808 than on a 510, wouldn't it use up an 808 faster than a Joye Mega xl?