Replay is a great feature. You literally vape and if you think ahhh that was a nice vape, you hit the replay feature and you get the exact same vape each time with TC baked in.
TC is slightly more complicated but anyone can use replay straightaway and therein lies it's appeal.
The new 80c DNA chip has replay for every type of coil but there are no individual TC profiles which could possibly mean replay is the future for DNA chips.