I've almost finished Unit 2 and I can tell you that there really isn't much maths at all. Most of it is simple addition, but occasionally you'll get questions that require a little bit more maths which you are taught to do and which are very easy. You'll be asked to calculate GST which should be very easy if you know how to move a decimal place, and more recently in accrual accounting there will be questions that require a little more maths, as well as some questions that give you formulas which are very easy to remember.
One very important piece of advice I have is to READ AND UNDERSTAND THE QUESTION VERY CAREFULLY. Seriously, ensure you understand every single word that the question is asking, because it could make a huge difference.
Also, if you ever need to remove or not include GST, such as on the income statement, ensure you always REMEMBER this because there are little things like this that you will forget on the SAC which will heavily affect your marks.
I know I said one piece of advice, but here's a third piece: focus on the theory part of the area of study once in a while, because you'll find that there may be a question where you learned the answer at the start of the area of study, and weeks later you've forgotten it, or you may just find that you forget the defintion of something very simple.
So far and overall, however, it is in my opinion a very easy subject and I would recommend choosing it. Good luck!