When choosing OCR software, I always think about the recognition accuracy and recognition speed.
The average time for recognition of a document less than 6 seconds. It is able to extract the text from an image of a document, and then save it as text file. I heard of them before, but I did not use it. The 10 free OCR software you suggest are great for me. The software runs on Mac, Windows and Linux and one license key allows to install the software on up to 2 machines regardless of the operating system. There is a free demo version available for evaluation.
Converting scanned and PDF files into text will be faster and easier by using one of these programs.