My wife and I both have unlocked S8 from Samsung and for the most part, couldn't notice any difference being on VoLTE. The one time I did, she was driving threw a town with horrible Sprint service. Her call started to sound pixelated but even before VoLTE, her calls sounded horrible while driving in it. We didn't drop connection but sounded like it could. I'm from the Columbus, OH market. Sent from my SM-G950U1 using Tapatalk