It looks like the $649 pricing for the M8 was only for a couple weeks, because now they've raised the price $50. Now there's no price difference between unlocked and the GPE, so if you're buying from now on, the GPE looks like a more feasible option.
Link: http://www.htc.com/us/go/buy-now-htc-one-m8/
Sent from my Nexus 5 using Tapatalk
Link: http://www.htc.com/us/go/buy-now-htc-one-m8/
Sent from my Nexus 5 using Tapatalk