Good to hear. It's working because you are using voltage less than 3.7 volts and well within the amp limit of the battery. If you were using higher voltages it could put a strain on the battery and you might not enjoy the full benefits of your Vamo.
That is the key to using the NCR 18650B. They work great in a regulated mod, firing standard resistance clearos in the 5 to 6 watt range.
I agree that they are not good for pulling the max 15 watts that a vamo is capable of, especially if the battery is not fully charged.
A nearly depleted NCR 18650B asked to fire 15 watts on a 1.8 ohm load is going to be over that battery's current rating.
I don't know if a vamo will even try to pull that kind of current out of a battery however. I use the 18650B in my eVic. It came with it.
Low wattage vaping they are suited for. Huge current, not so much.
The battery I would go to for a Vamo, SID, Zmax or any other 15 watt regulated mod would be the NCR 18650PF. it is a 2900mAh, 10a bat that works really well and lasts just as long as a 3400 mAh 18650B in less than demanding environments (edit: I mean using the 18650B in less than demanding vaping environments, low power only).
That 3400 mAh rating is a bit of hocus pocus anyway as it is attained by running the 18650B to voltages way below a voltage where a regulated mod is going to shut down anyway.