As a nearly "mil-spec" device, not only do they last forever, they hardly change with the fast pace of technology.
I think of Provari's as the B-52's of vaping. State of the art when they were introduced, still going strong, and still doing the job they were intended to do. And, just like BUFF crews love their ride, Provari owners adore their rigs.
While I would like to see them offer a VV/VW device with an information laden OLED screen (while maintaining their high quality and durability), the demand for "old faithful" is steady and that's a testament to the makers doing something well, doing it right, and not changing things every time someone else comes out with a new and shiny whizbang feature.
Why do you assume that selling an up to date model would mean Provape would not be able to continue to sell the 2.5. It doesn't have to be one or the other.