I bought this because I lost my Walter Piston volume on the same subject, and wanted reminding of a few things. And for that, I can well recommend this little book. Its size is really handy - it fits easily into a jacket pocket or handbag (well, you couldn't carry a Blatter, Adler or Piston around with you really). It also gives some helpful little tips, like the relative dynamic ranges in each instrument. It's not meant to be a textbook, and so if you're looking to learn orchestration for a modern outfit you'd be better off with something like the Blatter or Adler (which has a set of workbooks).
So all in all, it's a cute little handbook, with a friendly presentation (nice paper, crisp print, thoughtfully laid-out, etc). Great for dipping into as and when you can or need to, and small enough to carry around with you to rehearsals, seminars or perhaps working (with Sibelius, Finale, Notion etc) in a confined computer space.