I don't know, I've only had them a weekI'm not going to say that I don't believe you, however if your second MVP is already losing it's charge due to your heavy vaping profile, you must be going through 18xxx's like candy. The MVP uses a standard LiPo battery pack and it's charge/discharge profile is going to be the same as any 18xxx's. So even though the ProVari is still going strong, you still must be going through batteries like a mad man.
In your example, you get your ROI rather quickly, but you have to admit a 14ml a day vape, is not typical. For my vaping profile (2ml to 3ml a day) my ROI is going to be much longer than yours.
And if your profile is as extreme as you mention, then by all means, a "disposable" battery unit isn't for you. Anyone who wipes through LiIon batteries that quickly needs to replace them.
But my initial point stands. Going through 5 to 10 KR8080D's in a year back in 2010 was not unhead of, which made forking out $200.00 for a ProVari much easier. Your profile not withstanding, for a good portion of the vapers out there, the quality of products out there now, makes a ProVari ROI extend out to several years vs 1 year. It's something to keep in mind.

I probably will,,,,,,
next on my list to buy is an extended cap for my provari and several 18650s
as for 14 ml, yes, that's a lot,,,,,,,,,,,but I do vape a dual coil, and that accounts for at least some of it,,,,,,I think I was at about 10ml before I started using a dual coil.