This is a fascinating book that I can get lost in for hours. If you enjoy learning about the origins of words, then you will enjoy the Oxford Dictionary of English Etymology.
There are a few downsides to this book though. Firstly it was published in 1966 (46 years ago) and it badly needs updating. English has changed a great deal since 1966, and the lack of modern words and modern meanings is frustrating. I don't spend my time looking up rude words, but it is noticeable that there are no swear words in this dictionary.
There are frequent times when words are written in ancient Greek, which I imagine a more modern audience might struggle with.
There are too many abbreviations, which can make understanding some descriptions difficult. In some cases it isn't immediately clear whether words in the descriptions are translations of an ancient word or part of the author's explanation for the etymology.
It is extremely expensive for what it is.
If you realise that the dictionary has a few shortcomings, and money is no object for you, then I recommend buying it. It is probably the only book I own that I could never get bored of reading.
It is an interesting book to understand English words. Probably, it is a summary of etymological part of the Oxford English Dictionary. For foreign English learners, the book is the source of imagination and understanding of English language. It is not so expensive and is worth buying. It will help you learn English.