There’s a thread devoted to the topic here: Subconscious Limits Removal tag
In general the feedback is that the tags are more refined and powerful than the audios.
Whether once or twice is enough… I don’t know. The image on the SLR tag is an iceberg. Everything we think we know about how we think is barely scratching the surface. If one doesn’t identify root causes, patterns can repeat themselves. Maybe that’s why some users who want to dig deeper like to have SLR as an active effect (whether worn as a tag or audio looped) for a longer time. Tag would certainly be more convenient because it frees up your ears for other things.