This book is fantastic. I'm a first-year Japanese student, and while the rest of my class learns five Hiragana characters per class, I whipped up 46 flash cards using the mnemonic devices within this book and successfully memorized all of them in a week. I am now weeks ahead of the rest of my class, because I can now sight read Hiragana while everyone else still needs to use Roman characters.
I highly recommend this to any English-speaking westerner who is beginning to learn Hiragana and Katakana. Some reviewers complain that it doesn't examine the true basis for these characters, however that element is totally useless and tedious. Hiragana is used to represent sounds, and the quicker you learn it, the easier your life will be. Some of the mnemonic devices are extremely corny and far-fetched, however the results do not lie!
On a side note, if you are struggling with your Kanji, I highly recommend "Remembering the Kanji, Volume 1," by James W. Heisig.