I frequently work with PDF files/forms and need a good program for annotation. I've tried three so far: Preview, PDFPen and Acrobat Pro. Each can do some things I need, but none of them can do everything (at least not well) which is irritating. Preview gets close, but it doesn't allow me to place a PNG or JPG on top of a PDF. I have my signature stored as a PNG file, and it's very handy to just drop that on a line in the PDF. Preview also doesn't have a "freehand" pencil/drawing tool, which is bizarre. Acrobat also gets close, but either it doesn't allow me to place a JPG or PNG or I can't figure it out. Also, it places a line around text boxes (which I can't figure out how to change), and all text, freehand drawing, etc. is red (which I can't figure out how to change). PDFPen does everything I need, but I can't stand how it works. It's not intuitive and I find it difficult to use. Any other ideas?