Advantage: More stable air in your tires with temperature changes.
Disadvantage: You are paying for something that you can get for free by using regualr air instead.
Checking your tire pressure once a week isn't that hard to do. Why pay for nitrogen? Yes, race cars use it because 1psi can be the difference between winning($$$) and losing along with the high speeds they travel. But do you race your car and constantly travel at high speed? The temperature in the Philippines is also pretty stable and not like the States where you wake up and it's 0C and by noon it's 25C. Save the money use regular air, check your tire pressure once a week and while you are at it inspect your tires to make sure you have a safe vehicle.