Jeep Safari definately.
Why - All day trip including lunch, you drive through villages, see different areas, have fun off road with the odd water fight, if you are lucky you will get to see the Blue fish which are only found in this area of the world.
Quads are good but you only get about 90 minutes on them, ideal for a fun morning or afternoon but in my opnion the jeeps offers far better value for money.
If you can afford it do both.
Expect to get dirty on both trips so don't wear decent cloths.


Dave