I cannot imagine anyone who uses XWF not having Eric Zimmerman's XWFIM. Every time I use it, I wonder how I did without it. XWFIM is available through the XWF support forum. It's free, but you need a license for XWF to get it.
Eric constantly adds little things to it, much like Stefan adds 'little' things to X-Ways Forensics. One of the latest little additions is the selection box to "Include pre-release versions" which is pretty cool.
And if you haven't bought the XWF Guide yet and you use the XWFIM, just click the book's graphic and you can have the guide on your Kindle in about 30 seconds.