McGraw Hill, as well as Baron's, are not mentioned with enthusiasm among members. There's a reason for that.
I would immediately cease using those books and choose from more reliable sources, such as Kaplan
, Manhattan, and Powerscore. In terms of test simulations, the best is GMATPrep. A distant second would be Manhattan's six online tests. These two sources provide sufficient test practice.
GMAT Club Premium Membership - big benefits and savings