+1You're math is close but missing the remainder of the comparison. Next is cheaper in the first year, $1128 vs $1199. You went on to show the payoff of the phone with 6 remaining months and gave a total of $1260 but you forgot something. On next during those 6 months you pay $25 per month to have the device on your plan. In those same 6 months on the 2-year plan you pay $40 per month because you are not on Next. So if we do the math for the additional 6 months we have $1128+$132+$25x6=$1410. 2-year would be $1199+$40x6=$1439. You would save $29 by going with Next when looking at the 18 months. You're not being ripped.
In addition, the correct number is $21.64 per month but you rounded up to $22 which gives you about $7 in your favor on Next.
I have 3 phones on a plan and pay $190 a month for 30GB of Data (We had the double data). I previously had just 2 phones on the 700 minute plan, I had unlimited data and my other phone had the 3GB (Maybe 5, I don't remember) and was paying $220 just for that.
Now I have 3 phones and it's cheaper a month. On top of that, I'm going to do the Next plan for the 6S on two of my lines, but will be paying them off in full after a month because I don't want to finance a phone, personal preference.
I thought Next was a rip off as well (And it was in the beginning) but once ATT started giving significant monthly price reductions and made my plan cheaper, I was in. Plus now I can tether when I want, have unlimited minutes, and have rollover data.