It's a good book, but I am not sure if it's the book to read if you want to know even a little bit of the technical marvels he came up with. I found the book to be good enough to know the names of Tesla's inventions and who he was day-to-day, but not much more. Obviously if that's the main interest, this is a fine book.

On the other hand, if the idea is to learn more about his inventions, I'd recommend reading some of his own writing, e.g. Selected Tesla Writings: http://www.tfcbooks.com/tesla/contents.htm Lots of really amazing articles there. Check out this one, http://www.tfcbooks.com/tesla/1900-06-00.htm , it's one of my favourites.