Basically you'd be hard-pressed to hear a quality difference between the iOS data rips and the OST versions - it's not obvious.
For the most part, using the iOS data rips and their according loop data would be much more elegant and easier, the only exception being songs like "Into the Night" which already have an optimized loop (by yours truly) and is indeed better quality with the OST version. It should be noted however that, even though nobody will ever hear it due to the presence of an ogg.sli file, the iOS data rip version of "Into the Night" actually has an actual outro of sorts.
I also have done an optimized loop for "Light and Darkness" so it's possible that, in the future, it will be a similar case to "Into the Night" where the OST version will actually be better, but being a song with not-so-great dynamic range, it's also possible that the future iOS/Android data rip version will actually be better.