It's really bad.
I also spoke to several people to buy out my contract (ETF would be about $90 for the final month) and they said that I could do it to unlock phone but NOT to upgrade. In other words, I could be out of contract and have no obligation but AT&T won't take that as a reason to allow me to upgrade. That is how REALLY bad they want people to move onto the Next plan.
So I might have to go Next as well and drop my unlimited data (I only use 3GB/mo for both lines). But I might as well do it on the line that has the much longer contract length remaining. The phone companies want to get away from the whole subsidy model and Next, Edge etc are ways to do it. Might need to investigate T-mobile lol. But I think their coverage is terrible.
Looking at Next and assuming the charge is $40/mo and I save $10 on data fees, that's $30/mo * 12 or $360. But I don't get to sell phone. So every year I give ATT $360 for the latest and greatest model. Right now, I pay $400 up front but I sell my old one for about $200. So my annual cost of getting new phones is $200. So with next, you pay a $160 premium.