We used Miquon with our first.
I liked it with the exceptions of
1) it seemed like sometimes I had to explain how to do the page *and* how to do the actual math, because they were more creative and it wasn't always obvious to to the child what they were supposed to do on the page, even if they knew how to do the general math concept.
2) Maybe we weren't consistent enough (?) but when the books were all said and done, there was not a lot of retention, and no memorization of basic facts. I thought the no memorization wouldn't matter, but now that DS is in higher math, I see that really slows a child down not to have memorized basic things. (So we took some time off and did that.)
We used some Flash Kids workbooks from Barnes & Noble, and some Kumon here and there, which we liked, some books and pages more than others.
Then I started to use Rod & Staff with our third, who is in the 'first grade' and I am just thrilled. Is is simple, to the point, he gets it, and he loves it. I can't stop him from doing it! He raced thru the first book and is in the second (and last for the grade). My older two are doing Rod & Staff at their levels, and they love it too. I love that they are understanding, and are able to do it quickly because they are learning their facts. I love the simplicity and ease, and not having to explain everything, because they remember how to do it from the other pages like it. I would say it is very very straight forward and basic! Also, it is *very* inexpensive, so if you buy it and don't like it, it's not really a loss.