Cathy Duffy released a very thorough review of the Age 5-7 and Age 6-8 Math programs. A short excerpt is included below, but you can read the entire review by following the provided link.
From the review:
MBTP Math combines some of the best features found in other programs, but all in one place. It uses interactive methodology that adapts to the child to some extent. It uses multiple methods to convey each concept, so if a child doesn't grasp it the first time, other methods of presentation might be successful. Finally, manipulatives and games play a major role as instructional elements, a feature that is critical for some students and makes learning fun for others.