It might be airflow. Since the coils for eVods and ProTanks are set directly centered so that the air must flow around the coil, it might make for a tastier vape. I found it tough to get the airflow reliable and adequate in the RSST. Once I learned to set a micro coil on long legs directly in front of the air hole on the IGO-L (thanks to the micro coil masters), it's been all good sinceMy evods & protanks give better flavor & th than my Igo L & My RSST. why?
Both are good builds, Igo w/30ga & 3mm @ 1.5 ohm, RSST with 400 mesh and 30ga @ 1.8 ohm
same wattage, tested with butterscotch & cake (yellow) - evods beat both
....
But it might not be an airflow secret...just my guess