imho, I think, since this is Manjaro, user’s should consider Manjaro’s pamac. Since pamac uses the same library as pacman, it wouldn’t hurt to use either or both. Actually, since I’ve been using Manajaro this is the first time I recall seeing it recommended, and by @philm too. Where are these recommendations 
It was recently updated to V10. This doesn’t mean everything will be perfect, but development is active and issues appear to be addressed rapidly. We know when pamac is being updated, I wish it was more clearly communicated when pamac is being downgraded.
I use pacman, but pamac for AUR packages, but others I know use only pamac.
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