If TF Green has a flight that goes where you're heading it'll be an easier time. I don't find many good direct flights to where I need to go from TF Green, but the parking there is loads cheaper than Logan. The carpark is smaller too, so it's quick and easy to find your car. Terminal is easier to navigate and less crowded. I don't remember a ton in the way of food options at the terminal, but I think what was there was passable. Flight from TF Green tend to be more expensive too, so that's something to consider if it matters...