I think Saxon is for a somewhat mathy child who gets bored easily. It is spiral, and it keeps introducing new concepts before previous ones are solidified. This kept my ds extremely frustrated as he never felt like he knew anything. Saxon may be great for other children. It depends on your child and their learning style. For instance, my dd would be fine in any math program.
We are currently using R&S (grade 4) and are going to stick with it. It leads up to new concepts by gradually introducing the steps lesson by lesson. For instance, one wouldn't learn to simplify improper fractions all in one lesson. First, one would recognize to identify and name improper fractions. Only after this is done would one simply them (next lesson or possibly two lessons later). AND, the problems begin quite easy and lead up to difficult. The same would go for adding unlike fractions. First, lessons are given on identifying the lowest common multiple of two numbers. Then, a lesson is given on making equivalent fractions such that both have the lowest common denominator. After this is understood, then the fractions are added and subtracted beginning with EASY problems where only one of the denominator needs to be changed. The next lesson gives harder problems where both must be changed.
In a nutshell, R&S very meticulously leads the child through the steps of being able to solve problems. Nothing is left to figure out on their own. It is all explained in detail with much repetition. The book continuously reviews previous concepts.
I love the word problems because some (perhaps half) are not to be solved, but the child must give the information missing to be able to solve the problem, then tell what operation(s) would be necessary to solve the problem.
R&S has too many problems per lesson for a child to complete in my opinion. So, I simply assign 1/3 to 1/2 of the problems. If my child is having trouble understanding, I will spend 2 days on that lesson and he may do all of the problems. One would never run out of problems to assign with R&S.
R&S seems to be about 1 year behind Abeka but right on track with Saxon. In other words, Saxon 5/4 would be equivalent to R&S 4.
Blessings,
Penny