I've now got two Radius (Radii), and I have yet to use the onboard charging.
I have five of the same battery that came with the device (LGHGPooBrown), and I just swap my battery every four days when it dies.
I charge them on an external charger.
Also, I run my atomizers around 0.6 ohms, and firing them at 25 watts it close to 4.0 volts.
If she's using a Nautilus Mini, the coils are either 1.6 or 1.8 ohms.
If so, they usually bump up in resistance after usage.
My 1.6's usually peak around 1.8
My 1.8's usually peak around 2.0
With the math of 1.8/2.0 at 15-20 watts, she's above 5 volts, and 2.0 ohms at 20 watts is over 6 volts.
I can't personally recommend firing either Nautilus coil over 4.4 volts, which would be 2 ohms at 10 watts.
She's gotta be blowing through coils!
Of course, all of this is from my personal experience, using Nautilus coils on Provape devices...which means I'm getting exactly the power I dial my Provaris to.
I can't speak on how accurate her current mod is.
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My whole point here? To recommend The Classic as choice number one.
At their current price, getting her two would be effective, so she can always have one ready to go, plus having two different colors is an added bonus.
The menu is simple, and Provape-beginner friendly.
As some have stated here, the Radius would also be a great choice, especially if she's used to a box(ish) mod.
Even running my 0.6 builds at 25 watts (3.8 volts), I can get like 3-4 days on one battery.
If she had at least one other battery, and a good XTAR-VP2 charger ($25-30 on Amazon), I imagine she could be set all week.
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It all depends on how she vapes, and how comfortable she is with her current setup.
As you can tell, I'm very passionate about his subject, especially when it comes to newbies. I can't believe I took so long to buy my first Provape device (late 2013), but it truly helped me kick analog cigs for good.
As you can also tell, we are all here to help! And if a Provape device isn't the right device for her, none of us are too narrow minded to recommend another brand!
One last suggestion: Look into getting her a JUUL cigalike.
Even with all my fancy high end gear, I puff on a JUUL all day!