As used for concealment, I have found that different situations require different holsters.
A shoulder rig or cross-draw are great when having to sit for a while, but there are limits on when they can be used.
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
Life Member NRA
Life Member NAHC
Former President of the ECPT (Eifel Combat Pistol Team)