As a question - how big is everyone's backup getting with the imported items ?
This should be easy if you are using version 4 - set your autobackup to occur and save a copy to whatever drive you want - thumb drive, NAS, etc. and see how big.
We scan everything in and use a fairly good resolution so things are very readable (have seen other offices use low res - fuzzy, etc) and my files after 4-5 years are 3.66 gb in size. How does this compare ?