This book includes pretty much all of Bester's great works, plus a few lesser ones. Bester had a career of two halves. There was the pre-sixties era in which he produced the definitive version of many sub-categories of the genre, despite writing only a dozen or so short stories and two masterpiece novels.
Then there was the second era, in which he published another dozen or so short tales and more novels, all of which were dim reflections of his previous high points. This collection contains many shorter works from both of these periods and so they are uneven. Despite, or perhaps because, of this unevenness the tales are riveting. Second-rate Bester is better than anything most current sf authors are able to produce in the short form.
There is a sort of knowing naivety about his work. Some of the tales are corny, but all are done with panache. Bester can set up situations and explain his characters' motivations in a few high energy sentences. The result is that you are always carried along in an efficient and entertaining manner.
I think the reason modern sf short stories tend to be so dull is that authors have this need to say something profound about the human condition. This gets in the way of just telling a story. There's nothing profound here, nothing that you haven't come across hundreds of times elsewhere, but they are told well.