If it is something covered by a dogmatic decree of an ecumenical council, something consistently taught by the Church, then it is worth arguing about.
Beards aren't worth arguing about unless someone wants to deny us the right to grow and wear them (or until women start wanting them for themselves).
I have a tattoo on my right shoulder (lateral deltoid). It is an Orthodox three-bar cross inside a budded cross with IC inside the right arm of the budded cross and XC on the left. I believe that form is known as "St. Olga's Cross."
I decided to get the tattoo and had it done at a time when I had the flu and a high fever. I was also probably suffering from a bout of depression, but that's another story. Let's just say I wasn't thinking clearly.
I've never considered the tattoo a sin. I consider it a near-permanent reminder of my own poor judgment, especially when laboring at a body temp of 102 F.