Use of refcoordscaling in CHARMM and MARTINI

I notice that the refcoordscaling option in the mdp files from CHARMM-GUI have the following values:

com, in CHARMM

all, in MARTINI.

I understand the basic logic behind the use of this option, but I was wondering the reason for the difference among AA and CG. I am planning to do umbrella sampling in MARTINI, for a small molecule through a membrane. I was wondering if this option could have any adverse effect if used incorrectly.