xyzulu other than people with very small numbers of sites, I really don't see what people find so attractive about S3 backups.
When S3 is incremental, it's a coin toss it the backup system is using local resources to run the incremental check, or if it uses S3 resources... The last time I used Jetbackup incremental on S3 I got a $300 charge for 1 days backups, just from the millions upon millions of queries it was running on AWS checking for file changes, 90% of the cost was from queries lol
Object storage sucks if you have to manually grab files too. Most places don't have an easy utility for zipping "folders" on S3 (I actually only know of 1 that does, Wasabi, but they suck for other reasons like charging you for 90 days of storage on any file you upload, so you will incur huge costs every day from your retention settings). At least on Enhance backup server if you need to manually grab something it's extremely simple to ssh in, cd to a folder, zip what you want, then wget from the other server.
Heck, even for small numbers of sites if it's important enough might as well throw down for a little VPS instead of S3.
