Bitcoin Cash functions as peer to peer electronic currency with low fees. No need for Mastercard when using it.

How about using btsync and hosting your own cloud?

Yes, lots of suggestions to use BTSync. I am using it, just not for this particular use.

I want to backup and sync at the same time to an offsite server.

While I could roll my own solution, I want something that I can recommend to family/friends/my network (and that's congruent with their technical skills). :-)

I've been playing warsow on and off for some time now and am extremely happy for the update.