Decent backup tool for App Engine (Java)? With incremental backups

There's the BulkLoader which is nice but lacks many features of any normal bac开发者_如何学Gokup tool, as I can see, like incremental backups.

Another issue with this tool is that it doesn't always work properly - my app has ~2GB.

Bottom line - unreliable.

So, is there any good tool out there with incremental backups or should I implement on my own?

Thanks!

---

Found this tool: datastorebackup.com

Seems to be very good (tested a bit) - did anyone use it on a large site?