Agreed on this. ATT Next is the closest thing to buying a phone outright and adding it to AT&Ts network. You just don't pay it all up front.
I am on the exact same AT&T plan, but I think I have decided I am just going to start buying unlocked directly from apple. The NEXT plan is probably the better deal between it and the subsidized purchase option, but I would rather not take on additional monthly expenses if I can afford the out of pocket cost up front.
I just did the math on NEXT (Phone Price that they list under the NEXT Price list )
The Prices that I listed are 12 monthly payments
12 month Own phone the phone in 20 months
16 $326 32.50 monthly * 8 260 = 586
32 $450 37.50 * 8 300 = $750
64 $510 42.50 * 8 340 = $850
Even @ 20 month payment is still lower than Full unlocked
18 monthly payments
18 month Own the phone in 24
$500 16GB 27.09 * 6 more $164 = 564 you own the phone
$563 32GB 31.25 * 6 $188 $751 own the phone
$640 64GB 35.42 * 6 $213 $853 own the phone
And you only pay the Tax on the device plus Accessories that you want and tax on accessories of the time of the upgrade vs $40 upgrade fee / subsided 2 yr price
16GB $199 + 40+ accessories $35 + Full unit price tax ( California for sure) 64.00 = $340 - on 2 yr contract before you walk
32GB $299 + 40+ accessories $35 + Full unit price tax ( California for sure) 75.00 = $350 - on 2 yr contract before you walk
64GB $399 + 40+ accessories $35 + Full unit price tax ( California for sure) 85.00 = $360 - on 2 yr contract before you walk
Best Buy unlocked iPhones
16GB 700
32GB $900
64GB $1100