Using siunitx when submitting to APS

The APS journals use REVTeX as a somewhat-structured markup which can be mostly-automatically imported into their (non-TeX-based) internal system. They employ people to perform this conversion to their internal system for the tricky places where the conversion process fails (these people will reference the TeX-generated PDF in order to know what they should put in). It's very likely that the conversion scripts will not understand the siunitx commands. So, using siunitx has pros and cons:

Pros:

• You have an easier time with authoring your paper;
• People get to see nicely-formatted units in your author-prepared preprints (eg., on arXiv).

Cons:

• Your paper will take slightly longer in production before you receive your proofs;
• There is a slightly higher chance of errors being introduced in your units (due to the necessary manual intervention), meaning that you should pay close attention when you get back your proofs.

I recently emailed APS regarding this question. They said that it is acceptable to use the siunitx package.