VSO & VPDSD endorsements on US license

I have 2nd Mate unlimited, need to add Vessel Security Officer to my ticket.

Any benefit to also adding VPDSD? Or will VSO suffice for all the jobs out there?

See 46 CFR 15.1113(b).

If you don’t already have VPDSD then you shouldn’t be allowed to be sailing as mate right now unless you’re inland only.