At $849, the break even for me would be about 15-20 days use and that is a lot.
We live about 15 minutes from
Disneyland, on average we will go 4-7 days a month.
So, even on the low end, that is 48, more than pays for our pass.Granted some days we only go for a few hours, but that is an advantage of having a pass and living so close.
Our premium pass cost us $479, that would mean a difference of $374. At current prices, that means about an 8 day pass to Disney World (remember its the equivalent of adding water park, fun and more option as well as park hopper) to break even without accounting for any discounts such as free parking, etc.
Now, the new price for premium passes are $649, which means the difference would only be $200 for the premier, so the break even point would be even fewer days.
I think the premier pass is only for a limited number of people who live near either Disneyland or Disney World that normally would get a premium pass, but that likes to spend at least a week at the other resort.