The best software, easy to use and just pay once :)

Hidden amongst the sales "copy" online, the paid version allows you to convert to 300dpi PDF's. Well if you consider merely editing as a bonus, then there's that!

The free version does not work with page sizes OTHER than A4, so upgrade to NitroPDF

PDF Candy is an online PDF toolset of 47 services for successful processing of PDF files. The service is free for single-file operations and does not require an account. A desktop application is also offered,

They removed the ability to convert into jpeg in the free version

Enables four splitting modes, merges PDFs in any order, handles encrypted files with retained quality, intuitive interface for both basic and advanced tasks.

Yes I have tested it! And it was on a diagram with thin text in a pixel font, enclosed in circles.

The core product for PDF quality control (preflight), auto-correction and manual editing. This runs as a plug-in to Adobe Acrobat.

callas pdfToolbox Desktop is the easiest yet most powerful PDF preflight and correction application on the market. You can fix PDF problems during preflight or with a click on the button in the Switchboard.

Save ink. Save paper. Download fully functional free trial. No more printing blank pages. Remove unwanted text and images. Delete unwanted pages. Print multiple pages on a single sheet Print electronic letterhead. Archive print jobs.

Trial version prints a small banner on each p.