Hi there Anonymous,
I will be happy to assist you today. Yup SpiderOak really has excellent security and strong syncing but you can't save larger files as it is not designed to back up application data or operating system data" because those files are large, updated frequently and make your SpiderOak backup software work overtime.
If you just want to sync through other devices you can just use other services like (Dropbox, Mega, Megaup etc). Other services also provides security and syncing with the sharing functions. So by going for a expensive one and the one you can't use easily is just like wasting money for free.
So my advise is that you should use other services and you can also use there free plans. (MEGA gives you 50 GB of data storage and can be used for syncing and sharing with security).
I hope this thread helps you and if you have any other problems please reply to this thread I will be waiting for your reply.
Warm Regards,
Acme Gamer