Just about everyone prefers printed manuals. But they take too long to produce to really be feasible. Particularly not for software that gets an update about every 3-4 months that changes things. It takes longer than that to get the manual written, corrected laid-out and ready to print, let alone printing and distributing it.
A series of .pdfs addressing specific subjects would be very helpful though. Even with the hassle of needing to keep track of whether you’ve downloaded the proper one for your version of the program.