Yeah, I’ve been around the world a bit, too. The 2mm coils are still great for flavor and vapor, and I can do a micro-coil (1.5 mm) in a BCC where juice feed isn’t an issue, used to wind my PT coils on the 1.5 for a while with very good results. Someone in NT land send me a nano-coil once, think it was 1 mm, full contact, and I can’t imagine wicking something like that for tank duty, too much heat in the middle for a thin wick.
Wicking on the 2 mm isn’t bad, either, just gunks faster than I’d want it to. Very pleased at 2.4 mm, and I still have a full contact coil. My Radio tank is in need of re-wicking, I may tug the coils apart a bit and see if it’ll do even better with the nets. Has to be a “heat to wick volume” consideration going on, space the coil (or increase the diameter), that ratio goes down. With my contact coils, I get a very nice vape at 9-10 watts per coil, very efficient, expect I’ll have to bump up a little to match it with a spaced coil. Coils, wicks, or batteries, seems we’re always working on something.
By the way, if you go “out there,” micros are coils of less than 2 mm (I think) diameter, regardless of whether they’re contact coils or not. Better to stay in here, though, folks are way nicer.