I've experimented with various workflows of digitizing and have come up with the following observations:
Flatbed scanning is time consuming and tedious during the capture phase. It also has a lot of potential to damage the spine of books. However, once the capture phase is complete, the post process and organizing phase tends to move quickly. Most image adjustments can be made at the point of capture, resulting in much less to do in post process: very little image adjustment may be needed in post. Exceptions are when one scans multiple pages with a single pass (smaller books that can fit multiple pages on the flatbed). Then it becomes a question if one wants to split the scan into multiple digital pages.
Capturing with cameras can lead more flow in the capture phase. It might also need more gear to get the best results. If done with a cradle, it can be the least damaging to books. Depending on the quality of the capture, the post process phase can be more time consuming. One may need to correct for things like skew, bends in the page, proper alignment of the plane of focus, lens distortions, etc. Remember unlike text, music has a lot of lines, and wavy lines might not look that great in a digital copy. Also, cameras might be the best choice for oversized items, and things that don't fit on the flatbed. Think of manuscripts, orchestral scores, etc.
ADF or sheet feed scanner. Excellent option for loose sheets. Comes in handy when doing accompanying gigs and the soloist hands you a pile of loose sheet music.
If you are serious about using digital sheet music, I would recommend investing in a flatbed scanner, preferably with a double sided ADF. The book scanner option would be helpful if you have a high volume of sheet music.
Design an organization system right now for your digital sheet music. Don't just dump everything into one folder, or on your desktop, or rely on forScore to do the organization for you. In the future you might want to switch apps, or even use different apps depending on the reading device. Use a system of file naming and folder structure that works for you. Keep in mind, you may want to search for a file as your library grows, so use sensible filenames. Don't delay, now is the time to organize, before your digital library grows too large.
Have a backup to your digital device, especially if you intend to use digital sheet music in performance. Tech can break down, freeze, or decide to force updates at the most inconvenient times.
Think of how you will display the digital copy before you start scanning. Taking shortcuts in the capture and post process phases, might not lead to good usability when reading from a digital sheet.
Topic: Best way to scan sheet music for tablet use