My oldest is almost done w/ Saxon 3 and I'm buying Saxon 2 for my daughter. It gives us all we need to learn all the important math concepts. When going on to the next level we skip over many lessons that are review. There's plenty of review built into the worksheets anyway. Saxon is time consuming for the mom, but if you want to guarentee your child excels in math, Saxon.
They are asking me to review a product that I haven't even used. I bought them to prepare for the 2012-2013 school year starting in August. I'm sure these are similar to Saxon K and Saxon 1 that I have already used. I think they are great math programs but they aren't for everyone. They take at least 45 minutes to an hour to do the entire lesson per day. There is a lot of review and repetition.