@NCteacherlovescruising
Do you still have a flight to Madrid, then a flight BCN-FCO, or are you flying directly to FCO? We were talking a while back about complicated flight itineraries. I forget what you decided to do.
If directly to FCO, even changing flights in the US, I would agree on checking, especially when you are going to be six days in Rome after the flight. They will get the bags to you at the hotel. My only concern would be if we had tight connections or if we were moving to a different location or ship the next day. Going home we always check the suitcases.
Having said all of that, we just flew to Florida. We checked two identical bags at the same time. One went on our flight, the other one went on the following flight, so we had to sit at the airport to wait for it. Go figure. (Other than that, we have never had any problems checking bags.)
Make sure you put airtags in your bags whether you check them or not.
The Clarins would probably be cheaper in Europe than here. Check the prices as suggested above in amazon.it.