Its main problem is that it's a forty year old science book, so you're always wondering how much of it is out of date. For instance, it was written in the midst of a great reevaluation of radiocarbon dating, and many of the RC dates it presents hadn't yet been realigned to better match with absolute dating. (All Burgess's dates are clearly marked whether they're absolute or radiocarbon dates.) Burgess also abandons the Three Age terminology--Stone Age, Bronze Age and Iron Age--in favour of a series of discrete periods, each named after the location of their representative archaeological site. This is bewildering for the reader, as it means the familiar chronology is replaced with an array of names--the Overton period, Mount Pleasant period, Bedd Branwen period, Knighton Heath period and others--that really have no significance to him, and prevent him from having any real understanding of the relationships between them.
But I learnt a lot here. I was fascinated to learn that the picture I'd always been given of British/Irish (and, in fact, Continental European generally) prehistory--a picture of thin population densities and fairly regular population displacements and migrations--has been essentially abandoned by archaeaologists in favour of a prehistory that's more social organised and in which cultural changes arose more often from indigenous evolution than from the arrival of new populations.
The book does suffer from its first three chapters--145 pages out of the book's total 350--all being introductory in nature. Once we moved onto the chapters on specific topics (populations and social organisation, agriculture and economy, burial and ritual, etc.), it became much more of a pleasure to read.