Four Forces Notes and Text Books really DO suck!!!
My father just has / is using Four Forces DL notes to complete his CPL and I have to say they are useless.
The test exams have incorrect or multiple answers the books have pictures of make believe planes and they have a habit of giving EVERYTHING at least two titles. (I understand from him though that a couple of the lecturers on the consol course were really quite good so its not all bad)
He did actually pass all the exams he sat first time but thats just the kinda guy he is (plus he had notes from PPSC and Oxford to use).
But....... it must be said his entire course wrote to 4Forces before the exams stating that should anyone have resits to do then they DEMANDED the school be responsible for them due to shoody books.
Anyway hope this helps but remember it is just another opinion (Mine) and you may find others dont agree.
Meterology for Pilots - Mike Wickson (Excellent Book)