I think Borg would be a great solution for my use at home where I have a NAS on my LAN to provide local storage for the repository. But while traveling the world with my MacBook it doesn't cut it.
Arq looks good from that angle but I think would quickly cause my costs to overrun me. Having good backups is what gives me the confidence as a photographer to overcome my inner pack rat. Without good backups I'd never be able to ruthlessly delete images from my collection that don't exceed "okay" into "great". But because I know my images are backed up effectively forever I can really be honest in my art.
I personally use Arq against Google Cloud Storage. I have around 1TB, and I use it to back up several external drives in addition to my MacBook. (Arq is nice in that it backs up the drive if it's connected, but won't prune olds backups if it's not, unlike services such as Backblaze.)
I think I pay around $6-7/mo. I use a coldline bucket, which is the cheapest kind of bucket. Restoring is super fast (unlike Amazon Glacier, which I used previously) and not too expensive.
I wouldn't risk my amazon account on it, personally.
There are plenty of people who are storing absurd amounts of data [1]. If Amazon were cracking down on this, you'd hear it in /r/DataHoarder first.
The ToS [2] don't mention any size limitations. In fact, it says you can store pretty much any file as long as the data doesn't violate any laws, including copyright.
The only really worrying part is this:
3.2 Usage Restrictions and Limits. The Services are offered
in the United States. We may restrict access from
other locations. There may be limits on the types of
content you can store and share using the Services,
such as file types we do not support, and on the
number or type of devices you can use to access the
Services. We may impose other restrictions on use
of the Services.
[2] https://www.amazon.com/gp/help/customer/display.html/?nodeId...
- Client side encryption, with my key (and trust that Arq doesn't phone home). If that is an issue just pre encrypt the data before Arq backs it up.
- Use a storage provider of my choice, i.e. I'm confident that it is secure with Amazon S3 - no unknown shortcuttings.
- Multiple destinations possible.
- Open source tool capable of decrypting the data.
- Scanning of new / changed files takes could be faster and less demanding for the file system (on my Macs, Finder sometimes temporarily freezes when Arq is scanning for new / changed files)
- Mail reports for '0 errors' (all the time, so the mail reports for errors only are rather useless)
- Running in user context only, i.e., if you log out while your Mac is still running, the backup will not continue
- Loading of existing backups (reading / caching index) tends to be slow (and sometimes hangs)
- GUI does not scale up for many existing backups
With that being sad, you listed the major reasons to use Arq and all in all, I am a happy Arq user.
Switched to Sync.com a Toronto based company, with only Canadian servers. That means a lot to me as I've tried to remove myself from storing on American servers (just out of good practice on my part), and the service and support has been spectacular. I tried other options as well and this won me over.
If you have a realistic option (e.g. a fully supported solution) from another provider I'm all ears, but frankly SpiderOak has been good in that they have lost 0 data for me and have been able to successfully restore several times. If they could just double or triple the speed for uploading it'd be a huge boon to me, but realistically most of the places I've gone in the world being able to upload 2MB/s is faster than my local Internet is capable of.