You are correct that Bike Friday is smaller, somewhat lighter, and easier to get into a regular suitcase than a full-sized S&S coupled bike.
I have had both Bike Fridays and S&S coupled bikes. Part of your decision needs to be what you plan to do at the destination and for how long. Based on what you want to do, the S&S frame may be a better choice, or it could be that the Bike Friday is the better choice for you.