In reply to John1923:
I have all 3 mentioned in this thread.
I'd say the 7&8's is better than the font a bloc due to the amount of areas covered as well as it having less errors and clearer maps/directions.
The font a bloc is good for having the photo topos in it but there are a few errors such as lines and names and the maps aren't the best in comparison.
I second what the other guy said about Essential font - useful to getting to areas and also has the bonus of covering the classic easier problems which you obviously don't get in the 7&8's.