My dear go for CSS because I have seen the people that they are willing to clear the exam but they can't because some of them are being upper aged or they dont have another chance as they are economical stable but they wishes to clear the exam and serve this country and money is not every thing there are some thing like patriotism as like this country gave you a lot of things and it is time to pay back.
And by the way you can apply latter for abroad carrier don't miss the chance next is up to you be happy be positive and don't forget me in your precious prayers