I just spent an hour or so playing with my DX. It will work perfectly for my needs. Since I own a copy of Adobe Acrobat Pro, I can make all of the PDF documents I have searchable.
Also, since all of my client files are listed by client number and last name, it's pretty easy to find the file I need.
All my highlighting and notes, and even my photos for certain files, display clearly enough for me to read and study. I think my only complaint would be that it would be nice to be able to edit what a bookmark is called in a PDF document (so that, rather than "page 17" I could note that it is the "complaint" or my notes, or information such as that.
I haven't tried some of the other features that might making working with PDF a little easier on the DX, but on the whole, I like it and I'm keeping mine.