I vape mech mods and am just starting to wrap my head around this high power regulated stuff. Here's what I've got so far:
Watts = the amount of heat you put into the atty. This only influences wire temperature and vape temperature if you allow it to (wicking and air flow). Mostly it determines the amount of juice you vaporize per second of hit.
2, 1 ohm coils in parallel on a mech mod = 0.5 ohms which at 3.8 volts (4.2 volts minus voltage drop) makes around 29 watts.
2, 1 ohm coils in series = 2 ohms. This setup has the same coil surface area and mass as the example above and I can set the watts at whatever I want with a regulated mod (within reason). If I set it at 29 watts I should get pretty much the same vape from this 2 ohm regulated build as from a 0.5 ohm mech setup with a fresh battery.
And we thought VV vs VW was interesting