May I ask in what way exactly was it fine? Did you find the books easy to follow? Did any of your students feel a sense of sensory and cognitive overload?
I am curious becasue I have used Book 1 once and am re-evaluating its potential for future use. I found it quite difficult to use, one because I had never used anything based on a lexical syllabus, corpus linguistics and task based methodology. Secondly I did not even know of those terms till recently!!
Did you have to adapt the units at all?