I don't know yet if I like/need dual coils. I'm still too new to this. But its been recommended to me that my next step would be the Twist, but I can't afford a $25-30 battery every week along with all the other stuff.
So a 900 or 1000 pass through with a battery (why would one not want the battery?) wouldn't power a dual coil because it would be using a usb power cord. Do they make any that just plug into a wall outlet (I'd prefer that anyways)? What about lower resistance dual coils? I was using the ego Mega Clear DCT (1.6 ohms).
So everything points to a Provari. The drawback for me on the Provari it the 15 clicks to do something. No way I'll remember what I'm doing with all the clicking. I liked the Darwin, except for seems like they break down often and they aren't available. I'm more concerned about performance and ease of use than looks. As long as they don't look like a personal vibrator like some do.
I myself prefer dual coils;after trial and error and a little more time you'll know what works best for you.
As to passthroughs without batteries, they are cheaper and work fine for non dual coil setups. I'm not aware of any that just plug into the wall with no USB adapter. Low resistance dual coils such as 1.5 and 1.6 pull enough amps that you'll need that inline battery to use on PT.
I have heard good things about the twist, and agree that may be a good step. I'm not sure why you think you'll need new batteries every week or two as you should be able to get several months out of them. I have some six month old 18650s that are fine still...
Regarding the button, I moved from the Lavatube which had dedicated voltage buttons. I thought it might be a pain,.but in day to day usage I don't mind at all. If.I constantly brought up menus it might be annoying, but with how infrequently I do it hasn't been a big hassle and is far outweighed by the quality of the vape and device!
Sent from my phone; Please excuse typos / autocorrections.