if you have a Kanger ego batt it's regulated at 3.7v
most other egos put out 3.4 (+/-)
I like to stay in the 1.8Ω - 2.2Ω ballpark for non-variable volt ego batteries
JMO
- Kanger T3s/Mini T3s/MT3s
I am not using variable voltage. Im confused. I thought at lower voltage like a standard ego battery you would use lower resistance.
My girlfriend is running a 1.8 (which reads 1.9 on my MVP) and it works well. I had a 1.5 on my Protank and a eGo-T battery and I found the 1.5 didn't work as well as the 1.8. May have just been my taste or a messed up coil. Experiment. Get one of each. They tend to vary resistances from what they're supposed to be.
It really depends on what kind of battery you have. Classic eGos (made by Joyetech) are regulated at ~3.3-3.4v. If that's what you have, I recommend a 1.8Ω atomizer. 1.5Ω would be OK too.
If you have any of the newer, unregulated, eGo-class battery, they go from 4.2v fresh off the charger (briefly), then settle at 3.7v for most of the journey before finally reaching their cutoff point somewhere around 3.2 volts or so. So you're dealing with 3.7v--I like 2.0-2.2Ω on that voltage. 2.5Ω is in my opinion too high, especially since most Kanger coils run a bit higher (+0.1-0.2Ω) than advertised.
I got "generic" kanger coils ranging from 2.2 to 3.4 ohms... it sucks to not have reliable local dealers here in brazil, and every international shopping i do takes 1-2 months to arrive. Anyway, i think having an VV ego is cheap, almost cheap as an unregulated one, and experience is much better IMO.