If the prop has exactly one part, there's no benefit. But if the prop has subparts parented to the main item, there are at least two big advantages: 1. With CR2, you can scale the whole thing at once. Scaling just doesn't work right with a PP2. (There are ways around this, but they're harder than making a CR2.) 2. You can delete the whole thing at once.

My python page
My ShareCG freebies