We haven't tried either since based on reviews around here, we opted for Singapore Math and Beast Academy. Just in case DD ever has to go show competency on Common Core Math at some point in her life, I am making her do Singapore CC edition through 5th grade. She doesn't hate it but she prefers Beast Academy and in a year or so, we probably can start of AoPS.

http://www.artofproblemsolving.com

You can see if your DS is ready to start:

http://data.artofproblemsolving.com//products/diagnostics/prealgebra-pretest.pdf