Certainly this is the book for 18th century coins, unless you are mainly interested in one country like the UK or France -- in that case you would find more information more attractively laid out, along with other centuries, elsewhere, usually more cheaply too. But for its coverage of the world, including hugely complicated countries like Gemany, Italy and India, it is unbeatable. This 3rd edition is an improvement over earlier editions, because more pictures (especially of the smaller coins) and more obscurities have been included.
For users in countries which do not speak English, the conversions such as VF = TTB = BB =MBC are very useful !
The book is not difficult for foreigners to use.