Well worth getting IMHO. I'm only on the first book, but very informative. You really get a feeling of how an army functioned on campaign, the general fog of war as to where the enemy was and what they were up to etc.
I've just read St Paul's account of the Battle of Maleschitz (link) which made for fascinating reading. It was greatly helped by 2 different maps of the action, each broken down into 4 phases of the battle, which makes it easy to follow the action. Having read the account, it gives you some ideas for some 'what ifs?', such as if the Austrians had deployed forward as recommended by FM Browne, or the Austrian left wing actually moving when first requested.
Have now received the books. They are absolutely sumptuous, and fortunately have been translated from the C18th French into modern English idiom, making them a very good read. The maps, sketches and tables at the back came as a surprise. I was expecting about 20. There are over 200 in each volume - about 1/3 of each book. So far it is proving an easy and enjoyable read. The dust jacket artwork by Peter Dennis is pretty stunning as well. As a fan of the SYW Austrian army this has been a real find. Amazing to think that the pair of them are less than a Black Powder rule book.