My son is now in his junior year, and we're using eTAP and free-ed.net.
We've also used eTAP in the past and have returned to using it. This year, he's taking Earth Science, and what he likes is that the text is easy to understand, but if you want to study a topic in depth, extra resources are available via videos and references to other books/websites. All the core subjects are on the site, and he's segueing into using it for other subjects, too.
Another discovery he made on the website is that it can be used to study for the ACT and the SAT. If he clicks on links within the website, it takes him straight to the material that he needs to study.
Is there anyone else here who has tried eTAP?