We’re so glad PDF Studio is mentioned in this PCWorld article as one of the 5 cheaper alternatives to Adobe® Acrobat®!
Like Acrobat, Qoppa PDF Studio comes in two flavors. The cheaper Standard option ($89) covers the basics, including annotations, importing Word documents, watermarking, and merging/splitting files. The pricier Pro version (reviewed here) adds OCR and more advanced content editing and page assembly tools. If you just need markup features, the Standard version will be fine, but more regular content creators will likely do better with Pro.
Read the whole PCWorld article by Christopher Null:
PCWorld: 5 cheaper alternatives to Acrobat for PDF editing