Looks like you got the answer you were looking for already, but i dont care! When we bid a prime job, we generally bid to prime ALL bare drywall with whatever primer the job calls for (we're a preprite 200 fan). If the builder wants prep for wallpaper, we'll price that in with the finish coats as a single finish coat using Preprite PreWallcovering Primer.
I do not know any of the S-W coatings, so I can not address the
appropriateness of them.
One thing that we installers NEED on the walls (in this reduced VOC world) is 100% acrylic primers.
The long wet out and torsional pull while drying that wallpaper
subjects undercoatings to make less quality coatings inappropriate.
Also, many wall preps are the "tacky" type (Romans R-35, Calif Prep n size,
etc). These are great to hang on, but often present issues when stripped.
PLEASE communicate with the professional wallcovering installer about the
application of any coatings prior to installation, unless of course you are
willing to sign your name to the guarantee that there will be absolutely no
problems. (BTW, fixing a bad wallcovering job is way more expensive than
fixing a bad paint job)
Each installer will have his/her prefered primer and/or prep coat depending
on walls, wallcoverings, paste, and personal liking.