It is a great full coverage concealer, good for under eye circles and acne scars, and it blends evenly and naturally. I use it when I need heavier coverage and it typically lasts all day, but I live in the northern US. I wear it with foundation (Laura Mercier) and MAC Careblend powder on top.
The reason it might not be the product you are looking for is that it might not wear well by itself in high heat and humidity. I think it needs at least a setting powder on top, if not a primer underneath as well, to really stand up to heat and humidity for more than a couple hours. A friend of mine with oily skin used it for her summer wedding in Jamaica, and she wore it with primer, foundation, and setting powder, but then again, she was being extra careful because it was for her wedding. It did last all day and she looked flawless in her pictures, by the way!
I think it would be worth seeing if you can get a sample of this concealer from the MAC counter, at least enough for a couple days. I think it can stand up to oily skin, but the added issues of heat and humidity might be too much for it.