Good enough that I actually spent money on purchasing it, rather than just checking it out repeatedly from the library.
My problem with a lot of embroidery books is that they focus on covering so many techniques (Hardanger, counted cross stitch, ribbon work, etc.) that the instruction for any particular stitch suffers. This book does cover more than just free embroidery, but does not attempt to be encyclopedic, and therefore focuses on showing each stitch rather well.
There are certainly stitches that are missing from this collection, but this is an excellent reference.