His RX200S does support Arctic Fox firmware so it is possible for him to dial in his own Preheat Curve in VW mode... no temp control needed. On my RX300 it vapes surprisingly very similar to a DNA mod, at only a small fraction of the cost of a DNA mod... and more practical/convenient to set up when compared to a DNA mod.On a regulated mod with pre-heat temp control, yes! But, in general, with no temp control, ramp up time will be long. I use a kennedy roundhouse and a hexhom. I can adjust the voltage on my hexohm but not my mech. I was assuming his regulated devise didn't have pre-heat function. May be it does, I don't know. Either way, just about anything is safe on a regulated devise! On a .21 around 65, is what's recommended by ohms law.