Choose TXT for reading and research
TXT is easy to open, search and paste into a notes app. Use it for a written reference or first draft. It does not carry a synchronized subtitle timeline.
Choose SRT for a subtitle timeline
SRT stores numbered cues, time ranges and text. Many editors can import it. A valid file still needs a playback check for cue length, overlap and synchronization.
Keep source information alongside either file
Neither a text file nor a subtitle file proves the origin or accuracy of its contents. Save the video link and record corrections you make after listening.