Major Advantages
-More opportunities to live fun life (travel, take up hobbies) before re-joining the study grind.
-You can save up for uni expenses (rent, partying, HECS, food, fuel for car etc) with a full-time job during that year
Major Disadvantages
-You might ceebs going to uni after a whole year of not studying
-All your friends are a year above you and would 'leave you behind', so you'll have to start afresh socially when you go back to uni. (extremely hard for me, meeting people gives me anxiety -_- )