I'm going to be honest here. I've heard nothing but good things about the Rezound. I don't have it, but everyone I've heard has nothing but good things to say about the phone.
If I wasn't unlocked bootloader bound (Nexus), i'd probably go ahead and jump ship from my D1 to the Rezound. But a lot of D1 owners have been waiting for another vanilla phone and I can't pass that up.
As for your question, use your upgrade when you see a phone that will satisfy you for two years. Don't upgrade and then be bummed when 15 days later you decide it's not for you.
Sent from my CushZero using Tapatalk