Now that is a really good question Ling, and I would say yes but it really depends on your attitude. The course will probably teach you how much more there is to learn, and once you get past that and into the "I will learn continually" mode you will do just fine.
I do not teach diving for a living and I doubt I have ever broken even let alone profited financially, but I wouldn't trade any of it for anything. If you are not in the US and do not teach US citizens then your insurance fees should be way less than ours are, and it is the insurance that is more expensive than the dues.
Good luck, between now and the course dive all you can, but yes, at least in one instructor's opinion, it is worth it.