I am previous 2014 AUSMAT student. Now currently studying medicine in Manipal.
Sunway Ausmat is somewhere equivalent to Taylor's SAM. Both sit for the same Wace paper in the final. The difference is only in the allocation in internal/external exam.
1. For me 90 isn't actually hard to score in WACE. I got 91.60 , which i could did better if I understand my subject earlier. My friend from the same hometown/secondary school got 97.5, which he could understand the subject faster and efficient. So, if you did your homework, 90 is not a problem.
2. Our internal marks= class test + some assignments. So well, this requires your understanding in the subject well. Otherwise it may pull the marks down. Consistency is required in SAM/AUSMAT.
3. Allocate more time on studies, if you can't cope with your subject. Occasionally, have some fun when there are leisure time.
4. Don't listen to your lecturers, do your part. And you will find the fun in this course.
What I can say from this course, it is more easier than A-levels and STPM if you did your studies. Hope this enlightened you. ;D

then it is my mistake. I always thought that SAM= AUSMAT.

Then I don't know how tough is your sace exam + sam assessment course since you are implying that atar91 is low.

as in AUSMAT.. 50% is internal exam (School based assessment) + 50% is external exam (WACE final exam)= ATAR ranking

maybe you are better than me..