I have worked with Top Nothch (from fundamentals to 3) and summit 1 and 2, for 3 years.
The conversation examples are good.
The activities to do are sometimes to short (big pictures and little content sometimes, as I usually cover 2 pages with those books, no matter what is on those 2 pages).
The grammar is not the strongest part of them. It tends to be too concise, and sometimes it leaves many important details out. And the exercises tend to be either too simple or too complicated.
I would say the basic level books (fundamentals, TN1 and TN2) are good. But when it should add more content and to see a real progress in difficulty, it lacks consistency on the summit books.
Average book. If it is up to you, I would choose American Headway.
Hope it helps.