Personal preference.
Auto can be easier to learn as there is no gear changing and take off requires no clutch control. Once you obtain your auto licence however you cannot drive any other vehicle apart from auto for the probationary period of 3 years (can also be up to 4 years if you get red P’s for a whole year first). If you obtain your manual licence, you can drive both.
Note: Planning a career in the Police force, Army, Paramedic or Transport Industry and a lot of the trade industry requires a manual licence.