Unequivocally: 4-year degree. If you're going to shoulder thousands of dollars in student loans, it may as well be for something that would give you something to fall back onto if/when you are furloughed.
Whether you attend a flight school or not, you will earn the exact same ratings. You're better off shelling out $30,000 and get them on your own than spending $100,000 to get the same ratings through a a Riddle.
Good luck.