I wasn't aware of the $10 EDGE plan discount. I left before that started, I guess.
As for where to buy the phone, Amazon or Costco are generally the best prices, but sometimes bestbuy has a good sale going on. ($100 blue M7 the day it was released), I would never buy a phone from Verizon's corporate store or website.
The Verizon phone is unlocked by default. there is nothing the user needs to do. it's Verizon policy (yay!). As for the OTA upgrade, I'm pretty sure it doesn't matter, from what I've read, but I would just root the phone and flash the rooted update, anyway, to be safe.
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