I used to have a bias with non replaceable batteries, but the Darwin is holding out with no problems after 7 months so far, with the last version with blue screen/3 positionable arm swings. (not sure what the new version is at now)
It took me awhile to get used to the arm, because initially when I first saw it, thought it sucks due to having to use adapters for tanks and non removable batteries, I have to do the samething for certain tanks with the Provari as well with having to use adapters.
Both companies selling the Darwin or Provari are top notch which ever way you choose.
Agree with some posters here... with availabilities, the Darwin has a long wait time, where as the Provari is readily available.
When I use tanks on a Darwin, I just leave it "on" position, and the drainage on the batteries is not noticable as one would think.
I can use the Darwin as a passthru while recharging, Provari when the bats die, insert a fresh charged battery.
In long term usages, you save on battery purchases with using a Darwin, since its internal. Even with lith-ion batteries for PV's, they last quite awhile before they tend to die off for good...
Dial vs Button... both good in their own ways, no flaws either way.
It just comes down to availabilities.
Provari is almost always in stock, and the Darwin not in stock due to Evolv producing other products on the market.