I took the Manhattan GMAT
exams then an official test, and repeated the process again.
1- do not be discouraged by your score on exam 1. The instructors have informally told me you can add 50pts to your score. And honestly, you must realize you are just starting your prep work.
2. These tests are the harder and a bit more accurate than Kaplan
and PR in my opinion. (I bought all the books, even took a Kaplan class
in addition to MG)
3. In my opinion, you should add 50pts to test 1, add 20 pts to test 2, subtract 20 pts from test 3. I also was very strong in verbal on those exams, but was weak on the GMAT prep and official test.
hope this helps