Si Iniquitates and the Propers for the 28th Sunday

The sung propers of the 28th Sunday in Ordinary Time are all remarkable liturgical texts with justly famous settings having been composed throughout Catholic history.

Here are simple chanted versions from the Simple English Propers, which was lately reviewed by Dom Mark Daniel Kirby: "I heartily recommend Adam Bartlett's Simple English Propers. Put this book in the hands of your parishioners! And chant away! This extraordinary book has been met with widespread acclaim for the beauty and versatility of the music - and also for being the first generally accessible book of chanted propers in English for every parish."

You can sing the Mass or you can sing something else of your own choosing. Which choice is most faithful to the Roman Rite?