In my opinion, programs like that aren’t worth the money. Granted, I’ve never done one nor do I know what kind of student you are and what your goals are. If you buy the Real ACT Prep guide (Red Book) and do all the practice tests, and even some additional ones you can find online, you’ll see very good improvements in your scores.
Go through all the tests under timed conditions. Mark all the ones you got wrong, and try to figure out the correct answer on your own, without reading the explanation. Then write down the questions you get wrong in a notebook and write about why you got it wrong. Pick out any patters you may notice in the questions you get wrong.
I hope this helped, and feel free to message me if you need any help!