That's not a weird question at all. I paper scrapped for 10 years with CM product. I was still in paper when CM tried to make the shift over to the digital market. I have briefly used StoryBook, though I've never printed a book from the software. Too expensive. What you have said applies; the jpegs and pngs can be used in other places, and I believe you can import those from any other source.
I quit using CM digital product when they started charging so much for the software and their digital packs. The biggest drawback I find is that you have to order the book through them once it's finished. They do a great job, but are prohibitively expensive for me. I've done price comparison, and I've looked at a handful of their books, and I don't think they are "better enough" than the industry leaders in printing books (Shutterfly, MyPublisher, Blurb, WHCC) to justify the inordinate cost.
I use Photoshop Elements 6.0 primarily, I got it OEM for $35. And the neat thing about PSE is you can print your book anywhere; OR you can print at home. There is so much flexibility. If you run out of $$ and want to print a page at a time, you can. Or you can make a hardback or softcover book. There are endless possibilities to using your own design software.
Also, ease of use is a big factor---if you see other product you like (like here at DD!! the best in the world!!), I don't know how hard it is to put on your computer and sneak it into StoryBook.
If you are computer-savvy enough to use PSE or PSCS without undue frustration, I would consider making the switch. If you can, compare the cost of the StoryBooks and the cost of other printers. It's a personal decision. Believe me, I get constant flak for not using StoryBook; a good friend of mine has a mother and sister who are both CM consultants and they just don't get it.
Good luck! Hope to see you around here soon.
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Sarah
Equipment: Canon T2i (550D) with 18-55mm f/3.5-5.6, 55-250mm f/4-5.6, 50mm f/1.8, and 400mm f/5.6L lenses
Software: Windows 7, PSE 10 (Editor), PSE 6 (Organizer), and PSCS 4