We're on a 4-line family plan (all smartphones) and currently upgrade 2 lines every year (different contract expiration dates). I thought it'd be interesting to compare total cost for the old grandfathered rates that I used to have versus the new Mobile Share Value plans.
Old
$60 Base 700 minutes + line 1
$30 Family Unlimited Text
$30 line 1 data
$10 line 2 fee
$30 line 2 data
$10 line 3 fee
$30 line 3 data
$10 line 4 fee
$30 line 4 data
Plan Total: $240/mo or $5,760/2 yr
Upfront Device Cost (iPhone 32GB): $300/device or $1,200 total
Upgrade Fee: $36/line or $144 total
Total 2-year cost: $7,104
Current (Mobile Share 10GB, subsidized)
$120 Unlimited Talk, Unlimited Text, 10GB Data
$30 line 1 fee
$30 line 2 fee
$30 line 3 fee
$30 line 4 fee
Plan Total: $240/mo or $5,760/2 yr
Upfront Device Cost (iPhone 32GB): $300/device or $1,200 total
Upgrade Fee: $36/line or $144 total
Total 2-year cost: $7,104
New (Mobile Share Value 10GB, AT&T Next)
$100 Unlimited Talk, Unlimited Text, 10GB Data
$15 line 1 fee
$15 line 2 fee
$15 line 3 fee
$15 line 4 fee
Plan Total: $160/mo or $3,840/2 yr
Device Cost (iPhone 32GB): $37.50/line/mo or 2-year cost of $2,400 (with $600 balance forwarded for next year at $75/mo) or $3,000 (with device payoff)
Total 2-year cost: $6,240 (with $600 balance forwarded for next year at $75/mo) or $6,840 (with device payoff)
Sure, the savings isn't much but the latter offers far greater flexibility since you're not tied to a contract. Given the low resale/trade-in value on iPhones nowadays, trade-in via the Next program might actually be worth it for higher GB iPhones if you're the type who upgrades yearly.