kaplan full length exams are hard to say
certain sections are too hard and certain sections are too easy..
I feel Top score is pretty similar to what you will get on the real exam (Topscore maybe a bit easier..really depends on what you get on the exam)
I took CDAT twice (going to take US DAT soon)
By just using all kaplan material, I ended with 18AA (I usually get above 20 on kaplan exams)
I got 20AA on the second time by using DAT destroyer
Bottom line is, don't rely too much on Kaplan material