Just as a reference I did a similar analysis in the server recommendation thread for people with .enc files that were roughly 2GB which is average if you have been with AC for 3-5 years with all those IIs and what not. That's 12 hours on a DSL line. So my basically my recommendation is #1 have a strong onsite backup and local backup. #2 would be to backup the database offsite without imports and upload them to your offsite service of choice as well as keeping the imported items incremental. Incremental meaning only the stuff that was added that day gets uploaded rather than the entire folder daily.
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