I have an only and we have used Sonlight in varying degrees from the beginning. I don't think of it as "boxed" curriculum though. I use only the history/lit part and add in my "own" math, science, scriptures, etc. Sometimes I used the recommendations of Sonlight and sometimes I don't. The last two years we have used Sonlight 7 (I divided it in two). It was too hard for my barely average reader. Next year we will do Sonlight 100, but I will still do some of it as read alouds although that is not the way it is written.