Mine are in a folder called DevonThink Databases in a folder called DWA Data in Documents. I also use a sync store on my own WebDav Server running on my same iMac and that is how I sync my iOS devices. Was fiddly to get set up and still occasionally goes tits up but can be resurrected by shutting off sharing on the DAV folder in the Server App, restarting my machine and then resetting all sharing on and restarting again. Happens about once every 2-3 months or so.