If you enroll in a TPR online course then you get access to all 11 of their exams, whereas, if you don't have online access you most likely have access to either the review or complete exams through acquiring their complete set at a book store. I've taken a number of their exams already, and from what I've seen, the TPR course tests tend to get a little easier as you go along. From what I've heard from friends and have seen on the SDN community, the TPR demo exam and the review exams are a little on the harder side, while the complete tests with the exception of three are somewhat on par with taking course tests 4 & 5 in terms of difficulty. hope this helps!