What you get out of a scan is heavily dependent on the experience of the person working with it. Below is a scan I did of my MR Qui-Gon and some techniques I came up on how to use it.
using booleans as a slicer I can create top and side profiles to quickly generate flats for tracing copies of each section and revolve or loft out the base shape. The grip is easily traceable this way also to make boolean shapes. This is also a good way to get your asymm extactly.
You can also resurface a scan and generate nurbs curves to send to cad from Maya for example. Converting the poly edges to curves after you resurface your scan.
you can also get exact boolean shapes filling in the gaps of cut out with clean topology and extracting the shapes like this which can then be traced in cad or used any way you want.
or snap nurbs circles to your scan to get all the wonkyness you want and send those curves to cad.
extract and send to zbrush
Raw First pass MR scan from single 22mp stock camera.
One hour remake in Maya/Zbrush.
Scans can get you only what you know how to get out of them. If you want all the asym and wonkeyness to be copied you can get it if you know how. Hopefully this gives some people insight on different ways to use scans.