I loved them! We used them from first through 5th grade and I don't think the teacher's manuals are necessary but I did buy them all just because I tend to err on the safe side. I did have to look up a few answers to see if I understood what they were meaning, but it was very few and far between.
We used 2nd and 3rd and will be ordering 4th for next year. My DC love the stories and don't mind the workbooks. I feel they learned a TON from the workbooks even though we skipped most sections that have to do with pronunciation symbols. We also did a lot of the workbook orally just to speed things along. I found that the comprehension/vocab/phonics included in the workbooks taught my kids a lot. We also add in some Explode the Code to mix things up and this complements the Pathway Readers beautifully. This program helped things "click" with my dd and reading. I'd recommend it. I'm not sure about the older grades but for 2nd & 3rd, the TM was helpful but not necessary. For the minimal cost, I like being able to follow along with the answers and it is definitely helpful to me when I have them work orally. Just something else to think about - after the first book I realized it was hard for me to follow since I have them read the stories out loud. I started ordering a copy of each book for me as well so I could read along with them. The books are very inexpensive and this saved me a ton of getting up and figuring out where they were when they need help with a word. It helped their reading flow when I could just help them with the word immediately. Good luck deciding - it's never easy, is it?!
My son used these in 5th grade. Overall, I liked them a lot. They were appropriate for that reading level, inexpensive, user-friendly, they made it easy to figure grades, and they reinforced our family's conservative Christian values with one exception: A couple of the stories made it clear that their postition is that gun ownership should be against the law. It's just good to be aware of that. Good luck!
So far I've only used Pathways second grade readers. I needed the TM just because checking goes so much more quickly when I do, but there's also some extra little assignments here and there that were helpful. There are also suggestions about discussions, although of course they're aimed at a teacher of a class or at least a small group. I like how the first several levels follow the same families, the same way that my readers did when I was in primary school. We live in a rural area, so it's pretty easy for the kids to relate to the farm stories. What I'm not too crazy about is that the higher the grade levels go, the less teacher-help there is and the "tm" is just a student workbook with answers filled in, and no tests. Still, I have a student about to begin the third grade books. My usual favorite is CLE. I think the comprehension is more complex, and there is a LOT of instruction within the workbooks, with literary analysis coming in middle school that I didn't get until high school. But it's taught in such a gentle way that the kids don't really realize it's supposed to be "hard". Each workbook has two quizzes, a review, and a unit test. Almost every selection has a Bible lesson built in, with a memory verse that shares a theme with the story or poem, and it's explained at the level that the student can use it to apply to his/her own life. The fourth grade and up are constructed to take only a semester, so the student can use the second semester for other reading or projects, as you wish.