I think the modern ones are all fine for the basic stuff like that. For my work, it was the highly detailed low level stuff. Pre-flight checks/profiles, conten

I think the modern ones are all fine for the basic stuff like that. For my work, it was the highly detailed low level stuff. Pre-flight checks/profiles, content tree (object level, including text fragment) browsing, flattening, converting, transforming versions, and so on. It was indispensable for some of those operations, working in a printing business where clients would sometimes send in their own problematic PDFs which we'd need to adjust or inspect to find the error. (Favourite one: a font was embedded in a PDF that mapped a character using // in its name, which was "fine" on PDF, but on the printer's RIP was converted to postscript for one step, and // in postscript precedes an immediately evaluated name so it stopped parsing and tried to look for it and bombed out)