The only issues I have seem to be when I'm at home.
Sometimes, it takes a while to send/receive texts. Most of the time when this happens, I get anxious and instead of seeing how much of a delay there is, I simply update the profile and they all come quickly afterward. I've found that reprovisioning my phone using the ##SCRTN#(##72786#) dialer code while on CDMA tends to prevent this from happening for a greater amount of time.
Though, I did it a few days ago, it seems to be working okay now. We'll see how long it lasts.
PHONE: HTC One M8 Gunmetal Grey faux Harman-Kardon Edition
EARBUDS: Thinksound ts02