Right now I'm on AT&T 10GB with two paid off unsubsidized phones
$100-21 (21% Discount) +$15+15 = $109+ tax
Verizon is looking like this
$80-16 (20% discount) + $40 + $40 = $144 + Tax
One time $150/line for switching - $300 total
New phones at $299 each - $598 total (2 iPhone 6's 64GB)
Net I end up paying 35 more per month and $298 up front for the phones.
If Verizon would stop being greedy and offer the $25/line discount for bring you on phone. I would probably switch back. I'm using a Verizon iPhone 5 and a 5S that was original bought from Verizon. So both my phones can switch back with no problem.
Verizon does give you $25 per line if you bring your own phones (10GB or higher plan) ..It may not be listed but they will. You'd be at
$80 - 20% = $64 + $15 + $15 = $94+ tax
But you'd miss out on the $150 per line promotion if you bring your own phone.
I can 100% confirm that Verizon gives you $25 per line if you bring your own phone on the 10GB plans or higher because I have 2 Month to Month $25 discounts per line on my account from bringing my own phones.