It would depend on how much you roll vs how much you vape. Rolling might be equal to or less than ecigs, however I measure my monthly upkeep for my PV in a matter of 3 days.
3 days @ 2pk/cig/day = $38ish (12.50 for 2, it sucks.) This is a high average estimate, alot of times I can sum up my monthly upkeep in 2 days of smoking. Every so often it might be as high as 4 days depending on atties and such.
Weighing that after the initial cost investment is done, then it would depend on usage of rolled tobacco and how much one would get out of a pouch or can, whichever they bought, however I don't think a 6oz can of bugler would last me a month. That's roughly 2 days worth of analogs, cost wise. I believe they come with 200-250 papers in a 6oz can, can't remember exacts.. but that's a carton of normal cigs + a pack or two.
Convenience factor is another thing, it's far easier to buy a pack of analogs than roll them, and having rolled my own at points in my life, even with a roller, it's still much easier to use a PV over rolling. Faster, etc. Time consumption factor reduced.
Then there's the health risks obviously, you'll save money on doctor's visits.
Also, for my personal experience, there's saving money on the amount of extra crap I buy at the store when I go to get analogs. I can't speak for everyone, but drinks, maybe some noms, beers, etc. I don't have to go to the store anywhere near as much now, so I'm not tempted to buy all the extra stuff. Again, could just be me, but I'm certain I'm not the only one that buys a drink when getting smokes. Once Freedom Smokes (or insert whatever supplier) starts selling mountain dew, or chips, or some Arizona Teas Arnold Palmers and can ship and deliver in less than 20 minutes... then this goes out the window.